Going bananas over radiation

While doing some research on Thorium, I came across this interesting little fact that I wasn’t familiar with, so I thought I’d pass it along. Many people fear radiation, sometimes the fear is irrational, based on the erroneous concept that we live in a “radiation free lifestyle”. I’ll never forget one time when I showed my geiger counter to a neighbor who was shocked when it started clicking. She was horrified to learn that cosmic rays were in fact zipping right through her body right that very second. I didn’t have the heart to tell her about neutrinos.

But, along the same lines, this little factoid might drive some people “bananas” when they read it. But, it illustrates a fact of life: radiation is everywhere.

From Wikipedia:

A banana equivalent dose is a concept occasionally used by nuclear power proponents[1][2] to place in scale the dangers of radiation by comparing exposures to the radiation generated by a common banana.

Many foods are naturally radioactive, and bananas are particularly so, due to the radioactive potassium-40 they contain. The banana equivalent dose is the radiation exposure received by eating a single banana. Radiation leaks from nuclear plants are often measured in extraordinarily small units (the picocurie, a millionth of a millionth of a curie, is typical). By comparing the exposure from these events to a banana equivalent dose, a more intuitive assessment of the actual risk can sometimes be obtained.

The average radiologic profile of bananas is 3520 picocuries per kg, or roughly 520 picocuries per 150g banana.[3] The equivalent dose for 365 bananas (one per day for a year) is 3.6 millirems (36 μSv).

Bananas are radioactive enough to regularly cause false alarms on radiation sensors used to detect possible illegal smuggling of nuclear material at US ports.[4]

Another way to consider the concept is by comparing the risk from radiation-induced cancer to that from cancer from other sources. For instance, a radiation exposure of 10 mrems (10,000,000,000 picorems) increases your risk of death by about one in one million—the same risk as eating 40 tablespoons of peanut butter, or of smoking 1.4 cigarettes.[5]

After the Three Mile Island nuclear accident, the NRC detected radioactive iodine in local milk at levels of 20 picocuries/liter,[6] a dose much less than one would receive from ingesting a single banana. Thus a 12 fl oz glass of the slightly radioactive milk would have about 1/75th BED (banana equivalent dose).

Nearly all foods are slightly radioactive. All food sources combined expose a person to around 40 millirems per year on average, or more than 10% of the total dose from all natural and man-made sources.[7]

Some other foods that have above-average levels are potatoes, kidney beans, nuts, and sunflower seeds.[8] Among the most naturally radioactive food known are brazil nuts, with activity levels that can exceed 12,000 picocuries per kg.[9][10]

It has been suggested[11] that since the body homeostatically regulates the amount of potassium it contains, bananas do not cause a higher dose. However, the body takes time to remove excess potassium, time during which a dose is accumulating. In fact, the biological half-life of potassium is longer than it is for tritium,[12][13] a radioactive material sometimes leaked or intentionally vented in small quantities by nuclear plants. Also, bananas cause radiation exposure even when not ingested; for instance, standing next to a crate of bananas causes a measurable dose. Finally, the banana equivalent dose concept is about the prevalence of radiation sources in our food and environment, not about bananas specifically. Some foods (brazil nuts for example) are radioactive because of radium or other isotopes that the body does not keep under homeostatic regulation.[14]

  1. ^ http://www.ehs.unr.edu/ehs/LinkClick.aspx?fileticket=EgZI00myQRM%3D&tabid=62&mid=615
  2. ^ Weston, Luke. (2007-07-25) banana dose « Physical Insights. Enochthered.wordpress.com. Retrieved on 2010-10-19.
  3. ^ CRC Handbook on Radiation Measurement and Protection, Vol 1 p. 620 Table A.3.7.12, CRC Press, 1978
  4. ^ Issue Brief: Radiological and Nuclear Detection Devices. Nti.org. Retrieved on 2010-10-19.
  5. ^ Radiation and Risk. Physics.isu.edu. Retrieved on 2010-10-19.
  6. ^ A Brief Review of the Accident at Three Mile Island
  7. ^ Radiation. Risks and Realities, US Environmental Protection Agency
  8. ^ [1][dead link]
  9. ^ Brazil Nuts. Orau.org. Retrieved on 2010-10-19.
  10. ^ Natural Radioactivity. Physics.isu.edu. Retrieved on 2010-10-19.
  11. ^ Bananas are radioactive—But they aren’t a good way to explain radiation exposure. Boing Boing. Retrieved on 2010-10-19.
  12. ^ Rahola, T; Suomela, M (1975). “On biological half-life of potassium in man”. Annals of clinical research 7 (2): 62–5. PMID 1181976.
  13. ^ Environmental Health-Risk Assessment for Tritium Releases at the NTLF at LBNL: Chapter 2. Lbl.gov. Retrieved on 2010-10-19.
  14. ^ Brazil Nuts. Orau.org. Retrieved on 2010-10-19.
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193 thoughts on “Going bananas over radiation

  1. Well no wonder I glow after eating a loaf of my wifes banana bread. And here I thought I was just fat and happy. LOL!

  2. Hahaha good stuff!
    People are always amazed when I tell them that a nuclear power plant gets shut down when it leaks radiation equivalent to the amount a coal fired power plant puts out continuously…it puts the danger of nuclear in some much needed perspective…

  3. Thank goodness that the Australian bannana crop was wiped out by the recent cyclone (not really), humanity has been saved from lots of radiation. No if they could only do something about their AGW folks.

  4. Interesting timing of this article. You wrote “Bananas are radioactive enough to regularly cause false alarms on radiation sensors used to detect possible illegal smuggling of nuclear material at US ports.[4]”

    Last night, on “NCIS: Los Angeles”, the bad guys stole a nuclear weapon, and the NCIS crew was speculating that they may use a truck full of bananas to transport the weapon, thus making detection of the weapon harder. The thought was that the truck would be pulled over because it tripped the radiation sensors that had been deployed to look for the bomb, then the authorities would see all the bananas and let the truck go, not realizing there was a nuclear weapon underneath.

  5. One excellent way of sequestering banana radiation is by putting sliced banana into a mixture of flour, sugar, water and oil and subjecting the blend to high heat for a short period of time. When made in large batches and put into kilogram-size wrapped parcels they can be shipped to many individuals for safe storage, reducing the risk of terrorist’s acquisition of large quantities of the resource.

    Many studies have been done on this concept, and early studies resulted in the discovery of a replacement for expensive sandbags or concrete blocks for construction, affectionately called “fruitcake”. (unlike its impractical cousin “yellowcake”, “fruitcake” has an unlimited shelf life)

  6. As a nuclear engineer who formerly worked for Uncle Sam and now works in the commercial nuclear industry, it is frustrating to hear the same “crowd” who is so slow to skepticism in all other relams jump off the skeptical cliff about nuclear power. We continuously present facts that show the power source is safe when operated properly only to be rebutted by “What about Three Mile Island or Chernobyl?” Bad joke above, but accurate point about the late Sen Kennedy’s auto woes vs the nuclear power industry.

    The banana analogy, and the BED as a more specific measure, is a great way to get the point across. Discussing alphas, betas, and gammas, OH MY! just makes the uneducated eyes roll back. So thanks Anthony for spreading the word a little more.

    Finally, if you are impressed by the dose from a banana, DO NOT eat off of old orange FiestaWare ceramic plates. The pigment (at least at one time) was made with some higher-than-natural percentage of uranium oxide. Those plates can easily alarm a geiger counter that has no issues with the background field. Not a huge deal in the scheme of things, but will certainly open the eyes of someone who doesn’t understand radiation is everywhere.

  7. I will never again eat peanut butter toast and a banana before flying. You get everything searched. Trust me. I know.

    At an airport, not that long ago…

    After a fruitless trip through my luggage (pun intended), a pat down down and whatever she could think of the frustrated security agent looked up and said “Did you eat breakfast?” “Uh-huh” I said. She looked me straight in the eye and said “Peanut butter and bananas?.. Or are you smuggling?” I replied: “Peanut butter toast and a banana.” She told me to “Get lost!” and yelled her supervisor over and gave him a lecture about “crappy detectors”.

    True. I swear!

    The latest one was “Did you polish this jewelry while you were gone?” at the end of the search. Another sin apparently… That one set off the chemical sniffers and unfortunately it was quiet and they were bored so I got about 15 minutes worth of pat down and bags checking…

  8. Along the lines of advancing nuclear power, I’ve been thinking about a potential change.

    A fair chunk of getting permission for a nuclear site resides in the extensive geological survey and environmental impact assessment. And the budget for the lawsuits involving every detail overlooked in those studies.

    Put the actual core building on a barge. Put the ‘emergency shutdown’ cooling on the barge as well.

    The mammoth cooling towers are for the outer loop. And thus not part of ‘emergency cooling’. Nor are they dealing with radiologically active material.

    The major threat to a nuclear site – earthquakes – is pretty much relegated to a side issue at that point. Yes, it can damage the stuff that isn’t on the barge. But it essentially can not cause a radiological leak. The fact that the actual core ends up with a sizable moat and is thus also more difficult for a truck bomb or protestor to even reach is a bonus.

  9. Another interesting fact…
    A person living within 50 miles of a nuclear plant receives less radiation from it in a year than you get from eating one banana.

    from a highly recommended read
    Power to Save the World: The Truth About Nuclear Energy by Gwyneth Cravens

  10. They actually mentioned this last night on the TV show “NCIS Los Angeles.” It was suggested that someone smuggling a nuclear weapon could hide it in a truck full of bananas.

  11. An important note to remember though:
    Not all radiation is equivalent.

    Potassium is a beta- (electron) emitter.
    Cobalt 60, will give off a b- and/or gamma.
    Radon, found in bricks, will give off an alpha (helium) particle.

    As for protection, clothing will stop alpha, unless you ingest it, your dead skin layer will stop beta.

    gamma and neutron are considered whole body doses, because it will interact anywhere in the body.

    Alphas and neutrons will cause more damage than betas or gammas.

    After an element experiences decay, it loses mass and usually becomes another element.

  12. Mr. Watts you have something against scientific notation.

    REPLY: Huh? Lots of WUWT articles contain scientific notation. What’s your gripe here? – Anthony

  13. In the high mountains of Colorado, radiation exceeds three times the average in the USA, because of radon and granitic elements.

    Colorado natives have much longer life spans, compared to the USA mean.

    Causality or correlation?

  14. So wait. 40 Tbls of peanut butter increases my risk of death?

    *sigh* I’ll miss you, Favorite Midnight Snack…

  15. Another fun fact about bananas – they have five sides. Useless trivia, I know.

    I do like to tell people about bananas and the “banana-equivalent dose” whenever they start to rant about how evil radiation is, etc., etc.

  16. Get your elbows off the table (granite countertop). One of the best kept secrets for many decades up to recently was the radioactivity of granite building stone – notably the red and pink varieties which are high in potassium feldspar and mica. Some contain uranium that would be economic ores at approximately $100/lb for U3O8 (Indian Red from India I seem to recall was one of the high level ones). Working in a granite quarry one gets a full measure of the radioactivity. The Canadian Precambrian Shield has alternating volacanic and granite belts, the latter making up perhaps 75% of the area – all radioactive to a measurable degree. Even a spoonful of soil has all 92 elements in it so lets keep our cool – we must be in equilibrium with all this stuff around us. The link is for Czech building materials but applies for the whole world.

    http://bing.search.sympatico.ca/?q=radioactivity%20in%20building%20stone&mkt=en-ca&setLang=en-CA

    “All building materials that originate from minerals always contain a certain amount of radionuclides. These are mainly potassium, uranium, thorium and the radionuclides that are created as their radioactive decay chains. Of these, the most significant is radium (Ra-226). The Ra-226 presence in building materials causes exposure to persons living in dwellings – either by inhalation of radon daughters that decay from radium and release from the building material to indoor air, or by hard gamma radiation that releases from the building material as a consequence of the radioactive decay of the natural radionuclides to be present.”

  17. Many years back Blaine County in Idaho, home to Ketchum and Sun Valley and hundreds of idle rich declared itself a Nuclear Free Zone.

    We wondered how that worked out at the hospital and other medical centers among several location for potential radiation sources.

  18. Next time you are outside on a clear night look up…

    Nuclear energy is the single most common naturally occurring phenomena in our universe

  19. What amount of radiation does your body get from the potassium it contains and from others you live with? We ought to become hermits, but only after ensuring our cave is not carved out of potassium-rich granite, sandstone or shale.

  20. As a nuclear power plant worker, it always amazes me just how little people understand the concepts and actual exposure levels resulting from the plants. The sailors working on the flight decks of Aircraft Carriers routinely receive significantly higher doses from cosmic radiation and shine from the jets than the folks working in the nuclear reactor plant below deck.

  21. The human body is a system. It regulates itself. It has mechanisms to repair damage done by radiation. There is controversy about whether these mechanisms respond (increase in activity) when a person is exposed to radiation. It is possible that we live in a world with too little radiation. Sounds similar to CO2.

  22. I particularly like the comparison between the ‘radioactive’ milk after TMI and bananas. Unless my arithmetic is off, you’d have to drink about seven gallons of the milk to get the same dose as you would from eating one average banana. …or if you made a banana shake with that milk, less than 1.5% of the total dose you’d get would come from the milk.

  23. gcb says:
    February 16, 2011 at 10:05 am
    “Another fun fact about bananas – they have five sides. Useless trivia, I know.”

    I believe you would enjoy doing the old trick with a banana where you stick a needle into one of the ridges of the banana and swing the needle back and forth to slice the banana before peeling – my grandkids think I’m majic.

  24. Thanks Anthony for a well articulated note of radiation common sense.

    For non-Americans some unit translation:

    The average radiologic profile of bananas is 3520 picocuries per kg, or roughly 520 picocuries per 150g banana.[3] The equivalent dose for 365 bananas (one per day for a year) is 3.6 millirems (36 μSv).

    1 curie = 3.7 E+10 becquerels (Bq). One Bq is one disintegration per second.
    So 1 picoCurie (pCi) = 0.037 Bq. (One disintergration per 27 seconds.)
    So a banana contains 520 pCi or 19 Bq.

    Another way to consider the concept is by comparing the risk from radiation-induced cancer to that from cancer from other sources. For instance, a radiation exposure of 10 mrems (10,000,000,000 picorems) increases your risk of death by about one in one million—the same risk as eating 40 tablespoons of peanut butter, or of smoking 1.4 cigarettes.[5]

    This is the orthodoxy, but the risk of cancer from 10 mrems (100 uSv) is zero. There is a threshold of in the 10-100 mSv (mSv, not uSv) below which radiation causes zero cancer risk and probably slight health benefit.

  25. Some beta-emitting isotopes are more dangerous to be considered than others, if eaten. Some calcium isotopes are strong beta emitters, accumulate in bone, and have long half lives, so they sit and emit. A by-product of some of these (called a decay product) is an alpha-emitter. This radiation be a good or a bad thing, as mentioned, depending on one’s immunity. Sulfur 35 is actually dangerous, since it accumulates in important tissues, especially gonads.

  26. Truth is, that looking at volcano belching chlorine and fluor-rich smoke is “amazing”, while the steam coming off the cooling tower is “dangerous pollution”. Or three molecules of CO2 per 10,000 other molecules from 1750 are natural, but the fourth is again a “dangerous pollution”.
    Now understand how even almost harmless dirty bomb will make havoc in a modern society. Radiation, run!!

  27. Nostalgia: So my old C-D radiation survey meter is not the only one left? From the days of fallout shelters and “What to do in case of Nuclear attack” movies? Mine doesn’t click, only has a meter. If it moves off zero, say goodbye.

    Teller said something about getting more radiation from two women than from a nuclear power plant, so sleep with only one at a time.

    I think Chernoble killed more folks than TK’s car, so the bad joke may be obsolete.

  28. Run your counter down any pre-stressed concrete surface and listen to it hum. Used to do it when I was teaching first year geology to demonstrate the levels of radiation in the world around us. The teaching laboratory walls were alive with the sound of radiation. In fact most concretes will do it but pre-stressed is nice and high in potassium – as is the crust of our planet.

    And when it comes to high natural levels of radiation that population of Niue have been living with it for hundreds of generations. The limestone of the island is replete with both uranium and thorium. There is not a mutant in sight among the animals or plants either on land or in the Pacific.

  29. Jeff says: “don’t tell Michelle Obama, she’ll ban bananas …”

    Don’t tell Obama, either–He’ll want to regulate food by Federal fiat. Oh, wait…

  30. Back in my commercial nuclear power days, we would periodically get whole body scans to determine if we had exposure. One woman came up very (VERY) high in K-40. There was quite a bit of excitement surrounding whole thing until it was recognized she ate two bananas with her lunch….daily.

  31. Back in the ’80’s Psychology Today had a feature articla on common fears compared to the actual risk the feared phenominon represented. Everything from carcinogens in peanut butter (near the top risks) to Nuclear Power Plant emissions. Car travel vs. Air travel vs walking around a city block. The lowest risk, represented in the average days the risk shortened ones life-span, was living next door to a nuclear power plant.

    Toronto, Ontario has a science museum with a few articles in a glass box. The items included a red glazed plate, a brick, a cement block, and a pound of dirt from the perimeter of the Three Mile Island Unit 2 containment building. There was a geiger counter, much like the one pictured above, for masuring relative radiactive emissions. Nothing from the dirt, but I have to admit, I’ve decided not to buy any red fiesta ware.

  32. I never knew that bananas are beta emitters. I don’t know, but I’ve been told you can shield plutonium (an alpha emitter) with a sheet of notebook paper. On the other hand colbolt60 can shine gamma radiation right through your very soul. I live in the Rocky mountains at 7,000 ft above sea level. We’ve got lots of granite around. I don’t even think about my radiation exposure but I’m quite sure it’s higher than most of the US population. In fact, I was told when I first moved here that the road was paved with uranium mine tailings.

    A lot of folks would be shocked by the natural radiation that is emitted by the planet’s oceans (not to mention the mercury!). Radiation is ubiquitous. Ironically about your only escape is to spend 6 months aboard a submerged nuclear powered submarine. These guys have extremely low radiation exposure.

  33. bubbagyro – The only beta emitters for Ca are Ca-46 (0.004% abundance) and Ca-48 (0.187%). They are not a significant source of radiation. Perhaps you meant Sr-90, which is a byproduct of nuclear fission. Tons of were emitted in the Chernobyl accident and since Sr and Ca are in the same group, one will replace the other in bone structures. Sr-90 has a half-life of 28.8 years and is a principle cause for bone cancer to those exposed to it.

  34. A pal of mine arrived in JFK from LHR a few years back and set all the alarms off. Even after a strip search they still couldn’t work it out. Finally they let him offer an explanation, which was that he had been to hospital a day or so previously to have a barium meal, related to an ongoing medical investigation.

    All the more embarrassing as he was the skipper of the flight!

    Makes you think!

    I had never heard the banana explanation before – nice one Anthony.

  35. I read a few years ago that people who live in slightly elevated radiation environments (natural background radiation) are healthier and less prone to ailments like cancer. One city mentioned was Aberdeen Scotland, where the homes are largely built grom local grey granite that has a low level of radioactivity. The article suggested that American concern with low levels of radon may be misplaced.

  36. Denver has 3x the normal radiation exposure due to its proximity to the mountains. Yet cancer rates are lower there than on average. Who would have thought? Current theory alleges that the cellular DNA repair mechanisms are used more which allows for less errors to accumulate before repair, yielding more intact DNA.

  37. “don’t tell Michelle Obama, she’ll ban bananas …”

    There is no doubt who wears the pants in the family.

  38. What is amusing is that BANANA is an acroym for “build absolutely nothing anywhere near anything”. When people suggest going nuclear, the BANANA’s go, well, banana’s.

    If the ironic symetry were any more perfect, I’d weep.

  39. “The United States Bureau of Alcohol, Tobacco, and Firearms tests wine, gin, whisky, and vodka for radioactivity. If the product does not have sufficient radioactivity, it may not be legally sold in the United States.”

    Just to make sure it isn’t synthesized from crude oil!

  40. Re: nuclear power plants. Its not the radiation that they generate during operation but the (relatively low?) potential of mishaps and the especially acute problem of storage of long lived radioactive remains especially from decommission. Reviews of many of the mishaps reveal major cover ups of improper maintenance sometimes discovered only through the action of whistle blowers. I seem to recall that the Browns Ferry mishap was only one safety backup from a severe meltdown. I think that astute observation of that industry and the typical lack of trust of corporations in general (re the recent banking meltdown) is what probably makes most of the public nervous about nuclear reactors in general. It is also debatable if the standard design plants in use today would be economically viable without taxpayer subsidies for costs such as mishap insurance and waste disposal.

    http://www.lutins.org/nukes.html

    http://en.wikipedia.org/wiki/Browns_Ferry_Nuclear_Power_Plant

    http://www.iaea.org/Publications/Magazines/Bulletin/Bull314/31404684750.pdf

    http://www.usatoday.com/news/nation/2005-11-01-weapons-ocean_x.htm

    http://www.nrdc.org/nuclear/pnucpwr.asp

  41. Gary Pearse says:
    February 16, 2011 at 10:10 am
    Get your elbows off the table (granite countertop). One of the best kept secrets for many decades up to recently was the radioactivity of granite building stone –

    OH NO !
    I spend hours a day at huge granite table, about 2 meters by 5 meters.
    Ok it has a nice low expansion co-efficient ,but unfortunately it`s at er….ummm..just below waist height.
    Does anyone know where i can buy a pair of lead lined undercrackers, suitable for girding ones plums;)

  42. I’ll remember the banana comparison next time I try to convince one of my friends that nuclear power is the best way for the UK to head off energy supply problems. Even the ones open to my skeptical arguments about AGW doubt my view that the benefits of nuclear power today outweigh the risks, especially once Thorium is considered as a fuel source. Inevitably it comes down to the question why coal power stations won out over nuclear ones. Given the massive amounts of pollution the former used to produce, so goes the reasoning, the latter simply had to be massively worse to lose the competition.

    Very interesting post, well worth going off task for…

  43. @Dillion Allen

    DO NOT eat off of old orange FiestaWare ceramic plates.

    There was an article in The New Yorker many years ago about an artist who was working to come up with a suitable design for a marker to be placed over nuclear waste sites. He was struggling with the challenge of designing something that would be comprehensible to whoever is around to view it in 10,000 years or more. He wanted to include radioactive material in the design, but of course, it is not available on the market. So, he found a way to disintegrate the old red Fiestaware plates and extract the small amount of radioactive pigment they contain.

  44. Stop monkeying around, Anthony! The anti-nuke crowd will alternately go bananas and ape$h!t over this news! };>)

    Thanks for a most useful educational post!!!

  45. Living in Europe which has lots of nuclear power stations and is busily extending their life, possibly beyond what is wise, the problem is not the potential leakage – I have two within “exposure risk from leaks” range near me – but from the waste. It is currently being stuffed into disused Salt Mines deep beneath us, and while the long half life waste is a relatively small amount and, I believe, is adequately protected and dealt with, the “low level” waste is a vast pile and not as well protected and stored.

    Sadly, the morons of Greenpeace et al and the Campaign for Nuclear Disarmament failt o make a distinction between the two types. The vast majority of them also fail to realisethat radioactive radon gas, atural background radiation and cosmic rays – even before we get to the radioactive bananas sitting in the fruit bowl on the diningroom table, means we are all getting a daily dose of radiation we simply cannot avoid.

    OK, now I’ll take Brazil nuts off my list of favourites. Bananas I can handle…

  46. R John says:
    February 16, 2011 at 10:52 am

    No, I meant calcium, though Sr is the most potent of the bone adulterants.

    48Ca alone is present in the average human at about 12 grams! That is 12,000 mg per person. In bone, assuming that isotopic preferential deposition does not occur, and bone is represented by Ca3(PO4)2, that is around 5,000 ppb!

    With a half-life of 50 quintillion years this is serious stuff.

    (Seriously, it is very stable, and all of these atoms may emit only a few betas in our lifetime.)

    I was just being absurd, and showing how numbers can be confusing, maybe even frightening, to the average bear. Especially to the average Ph.D. professor.

  47. My favorite radiation is that which radiates from the Sun. My second favorite radiation is the heat energy which radiates from a wood fire on a cold winter’s night. My least favorite radiation? The sounds waves which radiate from my wife’s mouth every time she discovers I’ve used the credit card again.

  48. Chemists like me have our own analogies. During the review of an artficial sweetner someone complained that metabolytes of the product included a small amont of methanol, a toxic chemical. After several rounds with regulators another person pointed out that a 6 oz. Glass of orange juice contained 100x as much methanol, all natural and completely unregulated. The methanol issue was soon dropped.

  49. Reminds me of Jr. High School in the Fifties. One of my teachers became the county radiation civil service person. We learned to identify just about anything from the clicks it caused on the geiger counter.

  50. Linear extrapolation of radiation risks is not appropriate. If X dose will cause a 50% cancer risk increase , a .1X dose will not cause a 5% risk increase, and a .02X dose will not cause a 1% increase. In fact low dose radiation risks are wildly exaggerated by linear techniques. I suspect linear extrapolation of cigarette risks are also wrong, but in the case of radiation they are known to be not only wrong in size but in direction.

    The phenomena is known as radiation hormesis and is actually fairly well established. For the tyical American an increase in radiation exposure by a factor of 2-5 would in fact lower your cancer risk.

    Bananas are primarily gamma emitters. So even your lead lined undies won’t do much.
    The potassium-40 emission referred to should be a 1.46 MeV gamma ray.

    As for some types of radiation being more harmful… that is what the rem unit was for. I don’t think there is any hard rule for this, an alpha particle dose in the lungs can be more harmful than a high energy gamma ray dose externally.

  51. BFL says:
    February 16, 2011 at 11:21 am

    Nuclear waste disposal is a political, not a scientific problem. We can just dump them in a stable salt mine or into the Marianas trench with each encased in concrete and glass. End of problem. Remember that Ur is an element that is present in the ground and in ground water already. We don’t manufacture it. We collect it and concentrate it. The logical solution is to redilute it back where it came from—even better, my preference, the deep oceans, where it can slowly be redissolved over a few millennia, never exceeding background levels as it dissolves..

    [Oh, wait: isn't that how to make Godzilla!] LOL

  52. So where does this dose compare to the TSA backscatter machines.

    I hear way to much whining about radiation that equates to an extra 2 minutes at cruising altitude and wanted to see how many banana equivalents the scans were.

  53. Juraj V. says:
    February 16, 2011 at 10:35 am
    Truth is, that looking at volcano belching chlorine and fluor-rich smoke is “amazing”, while the steam coming off the cooling tower is “dangerous pollution”. Or three molecules of CO2 per 10,000 other molecules from 1750 are natural, but the fourth is again a “dangerous pollution”.
    Now understand how even almost harmless dirty bomb will make havoc in a modern society. Radiation, run!!

    Jason says:
    February 16, 2011 at 11:10 am
    Denver has 3x the normal radiation exposure due to its proximity to the mountains. Yet cancer rates are lower there than on average. Who would have thought? Current theory alleges that the cellular DNA repair mechanisms are used more which allows for less errors to accumulate before repair, yielding more intact DNA.
    Low level radiation up to about 100 mGy stimulate the immune system, partly from activity of heat shock proteins and other pathways, resulting in decreased – not increased – cancer mortality.

    Cancer deaths and mortality from low level radiation do not rest on experimental evidence but are in exactly the same category as CO2 global warming – a construct of computer modeling based on unfounded assumptions. Pure fiction.

    On that theme, coal fired power stations release more radioactivity into the environment than nuclear power plants, due to natural radioactivity in coal.

  54. Juraj V. says:
    February 16, 2011 at 10:35 am
    Truth is, that looking at volcano belching chlorine and fluor-rich smoke is “amazing”, while the steam coming off the cooling tower is “dangerous pollution”. Or three molecules of CO2 per 10,000 other molecules from 1750 are natural, but the fourth is again a “dangerous pollution”.
    Now understand how even almost harmless dirty bomb will make havoc in a modern society. Radiation, run!!

    On that theme, coal fired power stations release more radioactivity into the environment than nuclear stations, due to the radioactive content of coal.

  55. BFL: “…discovered only through the action of whistle blowers…”

    Drivel. All reportable incidents must be reported to the national nuclear regulator within the time limit specified, which is usually minutes or hours depending upon the nature of it.

    “…only one safety backup from a severe meltdown…”

    More drivel. This was an insulation fire unrelated to the reactor’s operating or shutdown systems. The plant’s shutdown systems were not impaired. What was impaired were government certification processes that approved an insulating material which was not fireproof.

    “..taxpayer subsidies for costs such as mishap insurance and waste disposal…”

    The mythmaking just never stops. All nuclear liability legislation has been tested by court challenges, and all court decisions have found that limited, sole liability does not constitute an economic benefit to the utility. With respect to waste disposal, there is no subsidy. Utilities have been paying disposal funds for decades and have now successfully sued the US federal government for its failure to deliver what has already been paid for.

  56. BFL says:
    “It is also debatable if the standard design plants in use today would be economically viable without taxpayer subsidies for costs such as mishap insurance and waste disposal.”

    No it’s not. Taxpayers do not subsidize disposal of spent nuclear fuel from nuclear power plants.

  57. bubbagyro says:
    February 16, 2011 at 11:51 am
    R John says:
    February 16, 2011 at 10:52 am

    No, I meant calcium, though Sr is the most potent of the bone adulterants.

    In your first post you mentioned alpha emitters. You must have been meaning Ra (224 or 226). 226Ra is in the natural 238U decay series, 2600y half life (224Ra has a few days half life and was once used medicinally).

    90Sr indeed is the most radiotoxic of the bone-seekers. Due to the longer range beta emission irradiation from marrow endocortical and trabecular surfaces, the entire haemopoietic marrow cavities are irradiated, including the hematic stem cells in the centers of the marrow sinuses. Thus both leukemia is caused (hits to the central stem cells) and osteosarcoma (hits to the bone lining cells). Ra226 by contrast emits alphas with 20-30 micron range which only irradiate the bone lining cells, causing osteosarcoma, but no leukemia since the marrow cavities are not traversed.

  58. Good fun,

    All the earth first ones who live in Aspen, Teluride, Durango, Leadville Colorado.
    Get them to one of the old down town buildings for tea and crumpets. Have G-counter ready after the drink a bit, turn it on, hold it up to the bricks (made with the mine tallings) ya, lots of watse U-238 etal.

    ttttttttttt real fast it does

  59. But, it illustrates a fact of life: radiation is everywhere.

    I think you meant to put “the average person doesn’t really know a lot about science” after the colon.

  60. Regarding C14 (AnonyMoose – February 16, 2011 at 10:46 am), Isaac Asimov wrote an essay back in the ’60s (I think) speculating that C14 decay might be a cause of cancer. He guesstimated the number of genes containing C14 in a human body and then the number daily that would be damaged by decay. I don’t remember the number (it’s been 40 years since I read the article), but it was astonishingly large – thousands? millions? per day.

  61. The Gray Monk says:
    February 16, 2011 at 11:48 am
    “Sadly, the morons of Greenpeace et al and the Campaign for Nuclear Disarmament failt o make a distinction between the two types.”

    It has never been the purpose of Greenpeace or the Greens to inform people; for Greenpeace, a scare means money, for the Greens, power.

  62. Your link to Wikipaedia for Brazil Nuts gives a more modest 1–7 pCi/g (40–260 Bq/kg). Lets assume 5 pCi/g or about 0.185 Bq/g as a reasonable mean. Further assume a modest 25 g, just under and ounce a day, for 365 days. I think this is not unreasonable. I try to eat at least this amount of nuts every day although not usually Brazil nuts. This amounts to an intake of about 68 Bq per year. This is radium however, the cancerous radiotoxin of the radium dial illuminators so more radiotoxic than K-40.

    Using ICRP Publication 68 dose coefficient of 2.8E-7 Sv/Bq for radium-226 gives the Brazil Nut Equivalent Dose, BNED, of 0.0000189 Sv or 0.0189 mSv or about 1.9 mrem/year. So even though the biomass intake is less it’s still of the same order of magnitude as your BED.

    Go back to your Wikilink for these nuts and note the supposed prostate cancer reducing properties of the high levels of selenium in Brazil nuts and all the other high value nutritional components of this food. Dr. Oz was touting larger intakes of Brazil Nuts as a pathway to good health and longevity last week. My wife thought we should buy lots of Brazil nuts,. I am happy with that because I like them.

    So I leave you with this little conundrum in risk management – which is what so much of safety and healthcare is all about. Should you eat them and take advantage of their health benefits or avoid them to minimize the risk of bone cancer.

  63. My sibling and I look rather different – I’m short and fair, sib is taller, leaner and much darker. When we were small, people would look at us and our parents and speculate. Some inquired as to which parent worked at the local nuclear facility. Others would ask what our Mom and Dad did for a living, and upon being told that one parent is a radiologist, the curious soul usually went “ah, thank you,” and gave us a knowing look. Actually, it is normal genetic variation derived from our very diverse family tree (Scots-Irish, English, Dutch, Cherokee, French).

  64. Antony, why dont you talk about Chernoby?

    Care to talk about and show photos of the children being born deformed?

    how long will the site remain radioactive?

    REPLY: get your own blog and you can talk about Chernobyl all you want, this thread is about Potassium-40 in bananas. – Anthony

  65. How will the horror of the radioactive banana be spread to the cowering masses of right-thinking people everywhere?

    By pressing a cellphone to the side of the skull, naturally.

    But first, it’s time for a lunch warmed up in the 25 year old office microwave.

  66. This topic brought up two memories.

    1. – Sensing the absurdity of the EPA standards, Dr. Michael Gough and I commissioned radiation experts to measure radiation levels in the U.S. Capitol building and compare them with the proposed Yucca Mountain standards. The Capitol contains a great deal of granite and marble building materials that naturally emit the same type of radiation as spent fuel.
    Our experts discovered that radiation dose rates at the Roger Williams statue, located between the Rotunda and Senate Chamber, are up to 65 times greater than what the EPA plans to allow at Yucca Mountain.
    The radiation-dose rate at the Williams statue also is up to 550 percent higher than the dose rate received at the fence-line of a nuke plant, and about 13,000 times higher than the average annual radiation dose from worldwide nuclear-energy production.
    http://www.foxnews.com/story/0,2933,21015,00.html

    2. – Back in the mid 70’s, some state legislator wanted a zero emission rate for any radioactive waste flow, until someone realized whiskey contains radioactive materials, so they would have to shut down all the bars.

  67. I work in the nuclear industry also, but don’t recall the Banana Dose Equivalent. What I have always gotten a kick out of is the example of sleeping next to your spouse or significant other – your annual dose of sleeping in the same bed with someone is roughly the same as getting a chest x-ray. Why? Because of the naturally occurring potassium 40 in each of us. We not only irradiate ourselves constantly, but also anyone that we are in very close proximity to.

    The other example I often use is a round trip flight from NY to LA & back, which is also about the equivalent of a chest x-ray.

    Or telling folks that the fact is you are safer actually working in a nuclear power plant than in your own home. Darned all those kids toys to trip over, stairs folks fall down, ladders…. You ARE literally safer and less likely to be injured or killed working in a nuclear power station than in the typical American home. Folks who work in nuclear facilities are also healthier than those who don’t – it’s called the ‘healthy worker effect.’ Who knows why, and there are a number of different theories on that one.

    Others here have mentioned the old Fiesta Ware – those are actually valuable as collectors items, but really do give off an amazingly large dose. Old watches with glow in the dark dials do also – they used to use tritium paint. One very innocuous item that is fun to use as an example of how incredibly sensitive even the oldest Geiger counters are, is a Colman lantern mantle. They’ll make a counter go from the slow tick tick of natural background radiation levels to screaming absolutely wild. Talk about an eye opener for many folks.

    Many years ago you could go to shoe stores and put your foot into a fluoroscope – and wiggle your toes and watch your skeleton bones move in the scope. They were used to fit your shoes. I’d LOVE to be able to play with one of those, but they gave you a really high dose and needless to say you can’t just get your hands on one and play with it anymore. http://www.orau.org/ptp/collection/shoefittingfluor/shoe.htm

    Frustrating regulatory factoid — The EPA limit for radon in drinking water is actually LOWER than the naturally occuring amount in some natural springs or water from natural aquifers. Seems to me that’s just yet another example of regulatory overkill, based on very unsound ‘science.’ There is zero evidence that those levels, even if that’s the only water a person had access to their entire lives, would cause any harm what-so-ever. But EPA protects us all from it none-the-less.

    Meanwhile, Anthony, if you knew how that estimate of “increased risk of death” from 10 mrem was determined you’d be appalled. Its strictly based on calculation and assumption – and those calculations have multiple different factors of conservatism thrown in (e.g., if we think it’s this much, double it in the direction of worse effect than we think, just to be safe), and the assumptions are of a linear dose effect, no threshold (virtually unheard of in biological systems)… with the primary data used being from acute high level exposures such as from Hiroshima and Nagasaki. Not from low level non-acute exposures.

    Which leads right into the whole “risk from radon exposure” b.s. that’s out there. That’s a very very similar situation for low level doses – all calculated, many questionable assumptions. There are only a very few areas of the country where radon exposure in homes is even the slightest concern – areas over the right type of bedrock. Even there you ONLY have a risk in relatively air tight basements or crawl spaces – and even then only if you spent many hours every day for a long time in those areas. Or very very rarely in the few super air tight homes that a few folks have built. For the most part even then the “risk” is questionable – there is a fair amount of solid experimental evidence of radiation hormesis – e.g., improved health or biological benefits to some radiation exposure that is significantly higher than we are typically exposed to.

    I recall one example I was told about by one of my professors back in grad school. An experiment was done using mice being exposed continuously to what would be considered to be a very high dose rate…. I wish I could recall the dose rate, but darned if I can – it was far higher than any typical nuclear power plant worker would be exposed to however if they lived in the plant 24/7/365. Far higher than normal background radiation rates. Still in the mRem range tho, not a super high dose. Anyhow, they were looking at litter size, fertility rates, mutations, birth defects, etc. They didn’t check life span tho (which would have taken a lot longer obviously). They continued for 20 generations this way, all being dosed continuously. Zero reduction in fertility rates, zero increase in any birth defects or notable health problems, just nothing – no detectable ill effects. In the last generation, however, they noticed one mouse that seemed entirely healthy but had a respiration rate that was half normal. It turned out that there was some mutation that allowed it’s oxygen transfer/usage to be twice as efficient. Go figure (and talk about intriguing as all heck, a biochemist or plenty of other researchers probably would have loved to get their hands on that mouse for study!!).

    One other thing that always amazes me – how many people seem to think that a single smidge, a tiny drop of radiation, will make an area deadly and radioactive for thousands of years and that there’s nothing that can be done about it. Many people don’t seem to realize that generally if something becomes contaminated (say areas within a nuclear power plant, or from a dirty bomb, or whatever), then it’s a relatively simple matter to just clean it up just as you would cleaning dust out of your house. Sure, with a few extra precautions to contain that ‘dust’ and not let any of it spread and to keep it from contacting the skin of those doing the cleaning, but still – often it’s very easy to clean up any contamination and then the area isn’t the least bit radioactive or dangerous any more. Other than those actually hurt or killed by the bomb blast itself (as they would be for any bomb, dirty or not), the most actual harm to humans from a dirty bomb would be from panic, NOT from the radiation. It’d be a pain to clean up, no question, but the panic from folks who don’t understand the real risks would be the killer, not any residual radiation.

    As to how easy cleanup of radiation contamination is in general – obviously there are exceptions and it depends on whether any of the radioactive material has become actually embedded in the structures involved, and the ease of clean up also depends on the type and amount of radiation involved… but the point is that many many people don’t realize that particulate radiation, e.g., ‘contamination,’ can typically be fairly easily removed with no ill effects and no residual radiation remaining. Reality is a world of difference from the all too common perception of “one drop of any type of radiation on this floor and it, the ground, the room, the building, all will be deadly for the next 10,000 years and nothing can be done to change that other than cordon off a large area around it and keep everyone out.”

    Oh, and speaking of hormesis – VERY interesting tidbit I ran across a few weeks ago. Apparently getting 3 CT scans of your chest over a few years actually cuts your risk of coming down with lung cancer by about 20%. CT scans give you a very high radiation dose (relatively speaking). http://opinion.financialpost.com/2010/11/05/lawrence-solomon-the-scan-that-cures/

    …..The $250-million study, jointly conducted by the National Cancer Institute and the American College of Radiology Imaging Network, involved more than 53,000 participants between the ages of 55 and 74 who had smoked a minimum of 30 “pack-years” (say, one pack a day for 30 years or two packs a day for 15 years). The study included ex-smokers who had quit within the previous 15 years and excluded all those who had had cancer in the previous five years, or who currently had any trace of cancer (except some skin cancers).

    In the study, called the National Lung Screening Trial, over the course of two years half of the participants received three standard chest X-rays and the other half received three low-dose CT scans to detect tumours. The participants were then followed for up to five years.

    The result? Those who received standard chest X-rays suffered 442 lung cancer deaths compared with 354 lung cancer deaths among those who received CT scans. This 20% difference is so robust — both in the number of lives that can potentially be saved in future and in the statistical likelihood that the results are valid — that the researchers stopped the study in order to publicize the results.

    Oh, and I almost forgot – last I knew you could still go and get your hormesis dose in “health spas” if you want to…. in, I think, either Wyoming or Montana – these are “spas” where you go into underground tunnels and stay there for awhile, specifically for the increased radiation dose you receive naturally from the increased levels of radon. There are similar ‘health spas’ in other nations too. I don’t know if this is still the case, but it used to be that you’d get a far higher dose there than would be allowed for mine workers or other occupational doses for people working in underground tunnels.

    Ah, well, what an amazing world we live in.

  68. Not only does the type of emission matter, but where it goes matters. For example, radioactive iodine can be efficiently collected in the thyroid.

    Generally speaking, external gamma emitters are a problem, but internal gamma emitters are not because most of the energy emitted from inside the body is absorbed outside the body. Gamma rays have low energy transfer characteristics.

    Alpha is the opposite extreme. High LET and a big problem if ingested, but the skin is enough protection for external exposure. Beta is intermediate. With external exposure, it penetrates the skin a little. Beta is more of a problem with internal exposure where most likely all of the energy emitted will be deposited within the body.

    The danger from radiation exposure is not so much in direct modification of DNA by breaking the phoshoribosyl backbone (and both strands have to break for repair to be problematic). The exception is internal alpha. The major problems are due to the production of highly reactive hydroxyl radicals derived from water made more potent by subsequent reaction with oxygen to create peroxide radicals. Both of these can travel a short distance through the medium surrounding DNA and modify the bases and backbone. This process greatly increases the effective cross-section of DNA for mutation-producing effects of radiation.

    40K emits a beta particle with about the same energy as 32P. We used to do DNA sequencing by labeling DNA enzymatically. I loved to hear the Geiger counter scream when I ran it over the gel. That meant I had a good sequence. I wasn’t worried at all about my exposure because I knew it wasn’t significant compared to my every day background dose from the natural abundance of 40K.

    People were irrationally scared of 32P. A market for 35S sequencing was developed. 35S emits a much weaker beta particle. I hated it. Not only were my sequences of poorer quality, but it was harder to detect 35S contamination. I considered 35S to be in fact more risky than 32P because it was harder to know where it was.

    Back to potassium…. Sea water has 40K at 300 pCi/L (http://www.physics.isu.edu/radinf/natural.htm). A long time ago, I was told by a radiation safety officer that sea water could technically fall into the category of radioactive waste. I tried to verify that claim today. I didn’t find any solid answer, but I wouldn’t be surprised if it turned out to be true.

  69. My God, no wonder my eyes glow in the dark! I eat a banana and 2 brazil nuts a day.
    I have it on good authority from a doctor friend that brazil nuts contain selenium which is a fantastic anti-oxidant and preventer of prostate cancer.

    I am still breathing so obviously the brazil nuts act as a radiation treatment as well as providing the benefits of selenium.

  70. @Taphonomic-

    Given that every taxpayer is also a consumer of electricity, I’d say that we do indeed subsidize the storage and disposal of spent reactor fuel.

  71. Re: Drivel:

    http://www.globalsubsidies.org/en/subsidy-watch/commentary/gambling-nuclear-power-how-public-money-fuels-industry

    http://www.nrdc.org/nuclear/pnucpwr.asp

    http://www.grist.org/article/nuclear-pork-enough-is-enough/

    Includes sloppy/fraudulent incidents including whistle blower:

    http://www.lutins.org/nukes.html

    Just to see how touch and go Brown’s Ferry REALLY was:

    http://www.ccnr.org/browns_ferry.html#ma

    http://en.wikipedia.org/wiki/Three_Mile_Island_accident_health_effects

    Local resident reports:
    The official figures are too low to account for the acute health effects reported by some local residents and documented in two books;[5][6] such health effects require exposure to at least 100,000 millirems (100 rems) to the whole body – 1000 times more than the official estimates.[7] The reported health effects are consistent with high doses of radiation, and comparable to the experiences of cancer patients undergoing radio-therapy,.[8] but have many other potential causes.[7] The effects included “metallic taste, erythema, nausea, vomiting, diarrhea, hair loss, deaths of pets and farm and wild animals, and damage to plants.”[9] Some local statistics showed dramatic one-year changes among the most vulnerable: “In Dauphin County, where the Three Mile Island plant is located, the 1979 death rate among infants under one year represented a 28 percent increase over that of 1978, and among infants under one month, the death rate increased by 54 percent.”[4]

    Health effects probably caused by media caused stress from scare stories, surely not from any cover up to alleviate insurance pay outs. Sarc/off

    Jeez, might actually try doing some Googling first, after all thats what it’s for.

  72. This is no laughing matter.

    A cascade of 5000 centrifuges can produce “weapons grade” bananas!

  73. DD More says:
    February 16, 2011 at 12:43 pm

    “Back in the mid 70′s, some state legislator wanted a zero emission rate for any radioactive waste flow, until someone realized whiskey contains radioactive materials, so they would have to shut down all the bars.”
    ___________________________________________________________
    No, Officer. I ain’t drunk…I’m radioactive. Y’all better get back in your car and drive away. Drive safely and have a nice day.

  74. This article freaked me out. I’m a programmer. I’ve never heard of this stuff. My chemistry teacher never talked about this. Well, maybe he did and I wasn’t listening. Bananas and peanut butter are radioactive? Potatoes? I suppose cows glow in the dark too? “glass of the slightly radioactive milk”??? These cows gotta be visible from the moon, no?

    And… and someone says my alcohol is radioactive? Gives a whole new meaning to alcohol poisoning.

    Seriously though, it’s not often that I read about something I’ve NEVER heard anything about AT ALL. NADA. ZILCH. I’m still freaked out. Every line I’m reading, I’m like “Whaaaaa???”. Damn, I feel stupid. How could I never have heard about this? I did know about gamma rays tho. But whatever. Luminiferous cows, man!

  75. I would luuuv to see the looks on people’s faces if they saw a plot of the ERAMS data. I viewed it as part of a human health risk assessment project once. It showed the amount of radiation floating around in the air during the 50s and 60s when nuclear weapon development was all the craze. The levels were off the chart … yep .. we were breathing many banans worth of radiation at that time. As the testing came to an end, levels dropped to about nothing. OH .. and there it was .. this tiny blip representing Chernobyl …. and 3 mile island didn’t even measure. Ever since then, I don’t worry much about it, and a huge fan of nuclear power.

    We NEED nuclear power … if we are ever going to become energy independent.

  76. I went on a visit to a nuclear power plant many years ago. Before entering the reactor building we were all checked for radiation with a hand held Geiger counter. It was clicking away randomly, which naturally had some folks concerned. The guide then held it up to his luminous watch (shows how long ago this was!), and it went crazy… A very effective way of putting peoples minds at rest!

  77. Fear of radiation is silly. The only way to go through life while not exposing yourself to natural radiation is to simply kill yourself .00001 seconds after birth. Even that is iffy, there’s no guarantee you’re not getting some while in the womb.

  78. Well I wouldn’t put a lot of stock in that use a truck load of bananas to hide your nuke in.

    K40 is a beta and gamma emitter, with a half life of 1.3 E+9 years. It is 0.0118% of natural Potassium, and emits an electron with 1.32 MeV energy. It can also capture an orbital electron and that is a 1.51MeV event. The electron emission (beta decay is accompanied by a 1.46 MeV gamma.

    The Beta electron, is not likely to penetrate far into organs or cells; the gamma is a bit more of a problem.

    But your nuke, is almost certain to be emitting fast neutrons; which are not going to look like bananas..

  79. Anthony,

    Its even worse. A 70kg man contains about 4.26kBq of Potassium 40 equivalent to 115,135 picocuries. Its obviously very important to make women aware of the potential radioactive risks associated with lovemaking with their partners :-)

  80. G. Karst says:
    Financial Post
    Lawrence Solomon: Radiation’s benefits

    So Lawrence Solomon discovers hormesis. What an enlightenment! Hormesis has been widely discussed in the nuclear industry for years. There is even a publication, the BELLE Newsletter, about hormetic effects including low levels of radiation. It has been around for about 20 years if I recollect rightly. Like Lawrence didn’t know it! He also knew that the very organizations and regulatory agencies responsible for the modern radiation protection framework, including the ICRP stated clearly that there was no way of knowing whether human response to radiation was linear no threshold or if, in fact, a threshold for the onset of detriment existed. Rethinking indeed!

    He and Energy Probe used LNT to beat up on the nuclear in Canada just to destroy the indsutry. Unlike reputable RP specialists his was more than a rational belief in LNT. He was happy to ally himself indiscriminantly with its most alarmist element including the likes of Helen Caldicott who attributes virtually every affliction and misfortune of mankind to the nuclear industry. Note any similarities to AGW alarmism?

    Then a terrible thing happened. The Ontario government decided to build windmills all over the landscape and phase out coal. This necessarily will means that energy costs will soar either through higher energy costs or subsidies recouped through taxation. This is what your duplicity has bought us Lawrence.

    Don’t believe Big Green’s epiphany about nuclear power. Don’t believe Lawrence’s either.

  81. BFL says:
    February 16, 2011 at 1:12 pm

    Re: Drivel:…

    Do you have a reputable website to link to, or just wikipedia and unsigned/un-accounted story pages?

  82. Radon gas is a decay product of both radioactive uranium and thorium which occur naturally in the soil. The outdoor radiation monitors that surround nuclear facilities regularly go off after a heavy rain because the radon in the air washes out and accumulates at ground level. Makes for some fun with the inexperienced health physics guys the first time it happens to them.

  83. If anyone is interested in deeper aspects of radiation and its health effects, I wrote this background paper for NWMO.ca. At the front of it are primers on radiation and radioactive waste, followed by health aspects, followed by a detailed appended list of studies. The appendix should be interesting to most intelligent people.

    http://www.nwmo.ca/3.2

  84. Well, that explains something about banana-benders (Queenslanders), anyway!

    It is also worth noting that certain rocks are far more radioactive than others. I recall discovering that granite is a particular offender in the this area. As it is formed lower down (under greater pressure, IIRC), the heavier elements such as Uranium tend to collect within this layer. The result is a greater amount of radiation.

    Not too important, but often people make nice granite fireplaces, bathrooms or kitchens, thus increasing their exposure to radiation. Some cities are largely built of granite, too. I seem to recall Glasgow is one, and the background radiation in such cities is about twice ‘normal’.

    Yes, this radiation is everywhere, and obviously entirely natural. We are lucky we are shielded from so much of it from the sun, or life would be very, very strange on Earth, if it made it at all. Probably odder than Queensland, even….

  85. By the way, anyone with a phobia against Fiesta ware, can ship it all to me. Please! I have one very interesting collection of radioactive things and proud of it.

  86. Alchemy says:
    February 16, 2011 at 12:42 pm

    How will the horror of the radioactive banana be spread to the cowering masses of right-thinking people everywhere?

    By pressing a cellphone to the side of the skull, naturally.

    But first, it’s time for a lunch warmed up in the 25 year old office microwave.

    That puts it all in perspective, it’s true!

  87. If I were to frequent anti-Nuke demonstrations, I’ve fantasized about handing out organic bananas to the participants and explain the joke later.

    Thanks for all the details, I hadn’t read the numbers before. I forget if I had heard of the BED, certainly worth remembering now.

    14C is also prevalent in lotsa stuff (like any plant grown outside). I think the potassium in the bananas is a lot stronger, but it worthwhile pointing out that to reduce one’s 14C content, one should eat food produced from CO2 derived from coal, oil, and natural gas combustion. Not wood!

    IIRC, some of the concern from at home exposure to radon came from a nuclear power plant worker who triggered the alarm going _into_ work one day.

    Also IIRC, much of the risk of radon came from studies of uranium miners. Many of them smoked, and radon daughters attached to the dust they inhaled and that lodged in their lungs giving them a radiation dose from the post-radon decay line. Wikipedia has some very nice decay chain graphics, see http://en.wikipedia.org/wiki/Radon . Once radon decays, it emit two more alphas and betas very quickly, hangs out at 210 Pb for a while (22.3 year half life) and that emits an alpha and two betas before stopping for good at 206Pb.

  88. Re: Jeremy, you mean like the fully signed and peer reviewed global warming sites???

    I’ll leave it up to you to peruse the many Google/Yahoo pages and let you decide which ones have the most logic….
    Having worked for DOD for decades, I’m just a bit familiar with Government practices in let’s say similar areas and as a result I tend to go with the “unsigned” “unaccounted for” sites over the “certified” government ones when they make sense. But, hey it’s your choice.

  89. bubbagyro says:
    February 16, 2011 at 11:58 am

    Nuclear waste disposal is a political, not a scientific problem. We can just dump them in a stable salt mine or into the Marianas trench with each encased in concrete and glass. End of problem. Remember that Ur is an element that is present in the ground and in ground water already. We don’t manufacture it. We collect it and concentrate it. The logical solution is to redilute it back where it came from—even better, my preference, the deep oceans, where it can slowly be redissolved over a few millennia, never exceeding background levels as it dissolves..

    It would be better to avoid a geologically active area like a trench. A practical solution was floated around 15 or so years ago that would have involved placing waste into stainless steel canisters and dumping them into thick oceanic mud a few hundred miles NW of Hawaii. The absence of oxygen at those depths would inhibit rusting. The greens pressured Clinton to sign a treaty banning such dumping–not that he needed much pressuring.

  90. I used to work in a UK nuclear power station as an industrial chemist, although we shared an office with Health Physics so I got a “dose” of that too.

    One day a very senior executive called a press conference to talk about nuclear power – a “hot” issue at the time. Prior to the start the Press helped themselves to bowls of chocolate Brazils that were positioned around the room.

    Once the conference was underway, the big man started talking about nuclear waste and especially the long term storage of low level waste. He compared the radiation levels with those in the chocolate brazils the press had been eating – our Low Level Wate is far less radioactive than the brazil nuts you have been enjoying. Not a single further brazil nut was eaten; several members of the Press tried to regurgitate the brazils they had already eaten and, I am told, the meeting ended in a degree of chaos.

    He made his point but the members of the Press were far from happy that they had been poisoned by all this radioactivity!

  91. I have a sizable collection of Vaseline glassware, sometimes called Depression glass which contain uranium. My oldest peice, an 1880 vase, contains between 5 and 10% uranium oxide. I wonder how many bananas worth of radiation I have in my display cabinet?

  92. Renaming the yield of the Hiroshima bomb to a 13 kilobanana detonation severely reduces its scare factor. Threatening to drop a 20 megabanana device on someone just doesn’t inspire much fear. So much for our strategic banana deterrent.

  93. You should promote these physics lectures for non-physics students at Berkeley. The entire series should be mandatory for anyone with a brain, here are radioactivity I + II, and nukes:

    There is also a lecture wrapping up all the subjects in one go, from the Physics for future president series (and a book by that title)

  94. There is substantial evidence that low level radiation has less of an effect than would be expected. The term “radiation hormesis” has been used and attempts have been made to explain how low level radiation may, perhaps, stimulate the immune system.

    There is a review dated 2002:

    Review: Cancer Risk from Low Level Radiation

    http://www.phyast.pitt.edu/~blc/Cancer_risk.pdf

    The review concludes that assuming risk is linear down with radiation dose down to zero radiation/zero ” … grossly overestimates the risk from low level radiation.”

    Despite this, the National Radiation Protection Board and other organisations still assume that all radiation is bad – the linear, no threshold, model.

  95. @Gras Albert says:
    February 16, 2011 at 10:10 am
    Next time you are outside on a clear night look up…

    Nuclear energy is the single most common naturally occurring phenomena in our universe

    —————-
    Watch it. You’ll get the electric universe nuts to come out from under their rocks.

  96. JER0ME said: February 16, 2011 at 2:16 pm
    “It is also worth noting that certain rocks are far more radioactive than others. I recall discovering that granite is a particular offender in the this area. As it is formed lower down (under greater pressure, IIRC), the heavier elements such as Uranium tend to collect within this layer. The result is a greater amount of radiation.”

    Correct result, wrong mechanism – try “granite” in Wiki as a start.

    “Some cities are largely built of granite, too. I seem to recall Glasgow is one, and the background radiation in such cities is about twice ‘normal’.”

    Edinburgh is the normal example of a granite city – built on and with granite. Aberdeen is the generally quoted twice ‘normal’ example – again a granite city. All in Scotland, of course.
    Alan (Currently a geology student from the UK)

  97. “Threatening to drop a 20 megabanana device on someone just doesn’t inspire much fear. So much for our strategic banana deterrent.”

    Somebody getting their “just desserts” this “Sundae”? (Sorry!)

  98. BFL says:
    February 16, 2011 at 3:04 pm

    Re: Jeremy, you mean like the fully signed and peer reviewed global warming sites???

    I’ll leave it up to you to peruse the many Google/Yahoo pages and let you decide which ones have the most logic….
    Having worked for DOD for decades…,

    Ah, but not the DOE? I’ve also worked with Gov’t for a long while now. I’m shocking myself to say this but there there are some gov’t agencies that are historically run very well, with nothing left to chance. DOE is one of them. BTW, name dropping will get you nowhere here.

    You have unsuccessfully deflected the question, btw. Do you have any reputable references? Wikipedia is not. Unsigned websites are not.

  99. ABC News just told me how the esteemed Center for Science in the Public Interest (CSPI), as announced by the esteemed Executive Director Michael Jacobson, is informing the public about the cancer risk posed by “caramel coloring” as found in sodas:

    http://abcnews.go.com/Health/cspi-caramel-coloring-cola-cancer-soft-drink-industry/story?id=12932008

    One of the chemicals found, 4-MEI, has made the infamous list: “Chemicals known to the State of California to cause cancer.”

    Death by bananas, or death by soda… Decisions, decisions…

    Meanwhile I’m waiting for Kalifornia to get around to banning electronics and pretty much all electrical devices, since they are known for producing ozone which is a well known potent cancer-causing chemical.

    Long Term Ozone Exposure Raises The Risk Of Dying From Lung Disease

    http://www.medicalnewstoday.com/articles/142097.php

    Dana Reeve, wife of Christopher Reeve (Superman), who was athletic and never smoked, died of lung cancer. Her husband was surrounded by electrical devices after his accident, leading to Dana being exposed to increased levels of ozone from electrical devices for about a decade. See? Proof!

    Someone alert the CSPI of the urgent need to immediately ban these producers of a known carcinogen. Think of the children!

  100. Has anyone googled “marijuana” and “radioactivity”? They blame it on the fertilizer, which you can buy at the local supermarket. Just don’t eat it (the fertilizer).

  101. @jojo

    “Antony, why dont you talk about Chernoby?”

    What’s to talk about? An inferior nuclear power plant of old crap communist design and run by a bunch of communist drunkards being drunk on duty . . . accident waiting to happen.

    “Care to talk about and show photos of the children being born deformed?”

    You mean from the ones who rather not pay for land and so disregard safety and go to to live on and of the waste land just because it is cheaper ‘an dirt cheap? Blame those idiots will ya.

    “how long will the site remain radioactive?”

    For ever since it was radioactive before they put a crappy designed crappy run nuclear power plant on the site in the first place.

    Of course would the accident have happened if the world since the 70’s hadn’t stopped R&D, and furthering, of everything civilian nuclear due to crazed hippie paranoia fear?

  102. re post by: Jeremy says: February 16, 2011 at 4:05 pm

    I’m shocking myself to say this but there there are some gov’t agencies that are historically run very well, with nothing left to chance. DOE is one of them.

    While there are a lot of good people in the DOE, some good aspects, and pockets here and there of well run groups – generally in comparison to decently run nuclear power utilities and decently run private companies I’d hardly say that DOE is anything close well run, let alone very well run. DOE suffers tremendously from the same problems most of the government does – an inability to get rid of really bad employees because of unionization (made worse than even in the private sector, because even professional ranks are unionized in the gov.), inability to police their own facilities/programs effectively or correct problems with any speed, horrendous waste of money, time, and resources, and so on. Well run surely isn’t a term I’d apply, unfortunately.

  103. From jojo on February 16, 2011 at 12:36 pm:

    how long will the site remain radioactive?

    Ecological Tour to Chernobyl Nuclear Power Plant

    http://www.tourkiev.com/chernobyltour/

    Twenty-three years after the Chernobyl nuclear disaster, Solo East Travel offers an ecological tour of the power plant. Visitors get to see a reactor, the “dead town” of Pripyat, and the “red forest” where pine trees turned reddish orange because of radiation.

    Two and three day tours are available. Stay at Chernobyl’s hotel, visit the Chernobyl Museum, see all the local attractions. Fun for the whole family!

    Take the tour, maybe you’ll get your answer there. Reasonable prices, a good boost for the local economy… What’s stopping you?

  104. Speaking of common things that are radioactive brings to mind another product you can buy in most sporting goods stores.

    Coleman Lantern Mantels for the old style gasoline fueled lanterns (and some propane models) are highly radioactive. The element that makes them glow a brilliant white when heated is thorium — yes that thorium.

    They will absolutely light up a geiger counter. We used to use them a readily available check sources, as the emit a broad spectrum, and will verify that almost any type of radiation detector is working.

    This is an example of common technology that has been around for over 100 years and most people have no clue. Thorium gas mantles, were developed in 1891 by an Austrian (Carl Auer von Welsbach).

    In practical terms it is insignificant. Direct exposure of the Thorium mantel to a geiger counter will result in hundreds to thousands of counts per minute, but as used by the consumer, by their very nature they are used at a distance (exposure drops of a the square of the change in distance — inverse square law), and they are inherently used in a situation where you would not want to be very close.

    A running fuel burning lantern is very very hot, so people stay back from them.
    If you used such a lantern every weekend for a year your dose would be on the order of 0.3 – 0.6 millirem per year.

    Here in Denver Colorado natural background radiation is about 2 mr/year depending on where you live. Just west of Denver in the Central City mining district pitchblend is found, and it is naturally radioactive (mined as a source of radium in the early 1900’s).

    You can pickup rocks off the ground that would easily trip radiation sensors. As a result it was necessary for folks concerned about detecting radioactive shipments or illicit shipments of radioactive material to collect data regarding these natural radioactive regions, and major buildings that included such materials in their construction.

    Fiesta ware is radioactive due to uranium which was commonly used for orange and yellow glazes in ceramics for many years. Older buildings with ceramic tiles with orange or yellow coloring are highly likely to have been made with glazes which contained uranium compounds to create their colored glazes.

    This is one of the areas where our school systems are absolutely incompetent, as they do not teach students that radiation is perfectly normal and they are exposed to it every day of their lives. They only perpetuate this with the absurd assumption that health effects of radiation exposure are linear even at very low doses rather than understanding that detectable health effects are not statistically significant at low exposures, and as mentioned above low radiation doses seem to actually be beneficial.

    Just like a sun burn, biological damage due to radiation exposure is a product or the rate of radiation, its duration, and what tissue is exposed.

    Larry
    Larry

  105. My daily dose of bananas has become too extensive recently due to crops being flattened by cyclones. You know, the ones that some say are being caused by our CO2 emissions.

    So our CO2 emissions are reducing my exposure to radiation. It’s all good. ;-)

  106. @ Jeremy: me thinks that you got the NRC mixed up with DOE. However I don’t put a lot of faith in any large government agency or corporation as their internal morality depends mostly upon who’s in charge at the time and it is too easy too hide misdemeanors or worse because of the authority level.
    Nothing wrong with Wikipedia depending on the subject and references. Sorry, but I like to look at opposing viewpoints from any sensible (determined from my experience of course) source and then draw my own conclusions, hopefully without emotion. Re a discussion I had once with a fellow about Reagan and what were his best accomplishments. Response, that he made Americans feel good about their country. I suggested that he research Reagan’s presidential stances and what actually took place under his administration, some of which actually set the course for the recent meltdown. All to no avail of course because of preformed opinions.
    To me, a part of smart living is, where possible and without making life too dull, controlling risk to life and limb, and most people working for government agencies have mandatory basic safety training that should instill this attitude to some degree (and yet some still ride motorcycles in big city traffic).
    So as far as radiation in food, there is not much that can be done to escape that or even the mercury contamination from coal fired power plants, even though these probably increase risk of cancers because some people are probably more genetically sensitive than others. However, I would NOT live next door to a Nuclear Power plant as I would not personally accept the increased risk based upon their history of incidents. Others may do so at their own statistical peril of course.

  107. @Dave Andrews says:
    February 16, 2011 at 1:49 pm “…Its even worse. A 70kg man contains about 4.26kBq of Potassium 40 equivalent to 115,135 picocuries. Its obviously very important to make women aware of the potential radioactive risks associated with lovemaking with their partners :-)…” Well, you’ve just given those Swedish trollops suing WikiLeaks dude (Assange?) for whatever a sure win and probable death penalty in Sweden!

    If you think your granite countertop is radioactive, and don’t have a scintillation counter or Geiger counter handy, find a Polaroid camera film, tape it to the counter top for a couple of days, then pull off the cover. Voila, you’ll see the location of every little speck of uraninite (U) or monazite (Th) and maybe even the potassium-bearing minerals (feldspars) showing up as bright spots. Their radioactivity exposes the film.

  108. @Dave Andrews says:
    February 16, 2011 at 1:49 pm “…Its even worse. A 70kg man contains about 4.26kBq of Potassium 40 equivalent to 115,135 picocuries. Its obviously very important to make women aware of the potential radioactive risks associated with lovemaking with their partners :-)….” Whoa, you’ve given those trollops in Sweden suing Assange (WikiLeaks dude) a conviction and probably a death sentence (buhbye, dude!).

    If you think your granite countertop is radioactive and you don’t have a scintillation counter or Geiger counter handy, get a piece of polaroid film (unopened frame) and tape it to the counter. After a couple of days, pull it up, peel the covering, and Voila! there will be a bright spot wherever there’s a bit of uraninite or monazite (and maybe some feldspars, residence of potassium). Their radioactivity exposes the film.

  109. However, I would NOT live next door to a Nuclear Power plant as I would not personally accept the increased risk based upon their history of incidents. Others may do so at their own statistical peril of course.

    BFL – Well, we all have our superstitions, don’t we? I guess this one is yours.

    Your “statistics” is the same kind of madness (i.e., bad math and incorrect assumptions) that lead people to play the lottery.

    For example, your “statistics” about the TMI accident are limited to what you can regurgitate from Wikipedia. Meanwhile, those of us who are actually familiar with the epidemiological literature know that you can’t cite one credible paper that has found, with any certainty, any adverse health effects due to radiation from that accident.

  110. Ric Werme says:

    “Once radon decays, it emit two more alphas and betas very quickly, hangs out at 210 Pb for a while (22.3 year half life) and that emits an alpha and two betas before stopping for good at 206Pb.”

    Forgive my ignorance, but how can something emit an alpha and still remain the same element?

  111. Another “former nuclear worker” (Engineering type) here, with plenty of radiation health physics experience, to give a few examples of ex-nuclear-poweris (the Latin term) radiation exposure:

    1. 400 miliRem per year of cosmic. (700 mR in Denver, 2500 mR if you are a commercial pilot, and roughly 4000 mR if you are a flight attendent.)

    2. CAT Scan (1) = 1.8 R

    3. Chest Xray = 100 mR

    4. GI Track/fluoroscope = 30R to 70R, (or 30,000 to 70,000 milliRem)

    5. EB Cancer treatment, about 20 to 30 R whole body, with 900 to 1200 R to the tumor. (Why it is effective!)

    Other radiation sources:

    A. Household Radon exposure – Jimmy Carter’s recommendation of tightening houses to 1/6 of an air exchange per hour would have increased the radon exposure such that the concomittant dose across the United States would have been equivalent to a Cherynoble accident once every 6 months…

    B. Coleman lamp mantles: Made with Thorium nitrate (now Yerbittium, not nearly as bright…mantles made in China and Pakistan still have good old Th !!!)

    C. “Salt Substitute” or Potasium Chloride, really raises the GM Counter nicely. Used to use this on Nuclear power talks given for a former employer. Got a LOT of attention when people realized they were EATING this…

    D. Cigarettes ! Polonium 210, in the Phosphate fertilizer used to grow commercial tobacco. 1 pack per day = whole body dose of 5R per year. Lung dose of 15R per year, could be actual cause of lung cancers, not the tars and cyclic aromatic hydrocarbons usually blamed!

    E. Mozanite Sands in Brazil: One stretch of beach, a few hundred miles long…gives you an Alpha dose of 1R per hour (that’s primarily SKIN, as alpha doesn’t penetrate) if you are lying on it. Great part about that is you can get a “tan” on both sides of your body at the same time!

    Now let’s talk about “high level nuclear waste”. If ALL the high level waste from commercial Nuclear plants in the USA were put in one place, it would not completely cover the football field at any stadium, and it would barely reach 70′ high.

    Dropping it in the subduction zone trench in the Bahaj, would send it to the center of the Earth in 100,000 years..where it would mix with the magma and never be noticed.

    Simple, straightforward, and YES we live in a very radioactive enviroment. Ask Dr. Svensmark how that changes CLIMATE!

    Max

  112. Chris says:
    February 16, 2011 at 7:38 pm

    Ric Werme says:

    “Once radon decays, it emit two more alphas and betas very quickly, hangs out at 210 Pb for a while (22.3 year half life) and that emits an alpha and two betas before stopping for good at 206Pb.”

    Forgive my ignorance, but how can something emit an alpha and still remain the same element?

    It doesn’t, but his intention was to indicate that once the initial radon atom decay occurs (which may be delayed for some period of time since it has a 3.8 day half life), the subsequent daughter products follow a relatively rapid series of decays, followed by some longer decay times from pb210 on down the decay chain.

    Imprecise wording perhaps, but the intent was clear that the reference was to the progression of the decay chain starting with radon.

    http://www.ead.anl.gov/pub/doc/natural-decay-series.pdf

    Larry

  113. I skipped most of the comments, but if no one has mentioned salt substitute yet, I will. Salt substitute is mostly KCl which is similar chemically to NaCl or regular salt. It tastes similar and can be bought at most grocery stores. I used to use it as a radioactive check source for my gamma spectrometer. It is pretty toasty if you get close to a bottle with a geiger counter.

  114. From Max Hugoson on February 16, 2011 at 7:58 pm:

    C. “Salt Substitute” or Potasium Chloride, really raises the GM Counter nicely. Used to use this on Nuclear power talks given for a former employer. Got a LOT of attention when people realized they were EATING this…

    Note the recent push with foods to reduce sodium intake, by replacing common sodium chloride with “sea salt.” And I keep thinking of all the assorted minerals that are dissolved in the sea, that end up in “sea salt” after removing the water from the “sea soup” (which contains numerous waste products from aquatic life), of which there are substances that virtually No One would willingly consume if they could avoid it. Like uranium, and just about every radioactive isotope on this planet…

  115. Holy cow! I learned something new today. And my mother used to tell me to eat bananas, because they had lots of potassium that was good for me. I wonder what she would have said if she found out that potassium was radioactive. But this post relates an obvious truth: from my computer screen to bananas, radiation is EVERYWHERE! So don’t worry about it. Unless you get way too much of it.

  116. The equipment used to measure radioactive stuff is soooo sensitive, however when
    needle moves, and/or speaker squawked it must be bad, bad BAD.
    Conflict bananas….worser than conflict diamonds.
    Ditching nukes in banana shipments ^ crap… Unknown known, so far.
    The following line is great…

    “I didn’t have the heart to tell her about neutrinos.”

    Me I have low tact, how about the massive dose passengers receive in an aircraft ride. Wonder if she has a passport?
    Fred Finn traveled at 60,000 feet looks ok.

    http://heritageconcorde.com/?page_id=4541

    To bad we didn’t freak out like France did in the 70’s. We have 80% of our electric power produced by Nuclear Power TODAY. Oh wait….

  117. Taught this stuff for 25 years.

    Imagine 1 carbon-14 atom. It will only emit radiation once – more on this below. There is a 50-50 chance this one atom will emit its radiation in a 5500 year period (half-life). So what is that one atom doing the rest of the time? Nothing. Acting like carbon, smelling like carbon and going out on dates like carbon wants to do. One day it will emit its radiation, then never emit radiation again. Statisticians and rad professionals leave me alone on this next bit, as it is presented to make it understandable. So you need at least 10,000 carbon-14 atoms to get 1 disintegration per year. 10, ooo x 365 x 24 x 60 x 60 atoms to get 1 disintegration per second (1 Bq). That is 3 E11 C-14 atoms to get 1 Bq. The longer the half-life, the more atoms it takes to get any significant disintegrations. See the table below.

    Back to the one C-14 atom. It has too many neutrons in the nucleus. It is not comfortable with that fact. Imagine buttons on a too tight shirt. One day one of those neutrons (buttons) pops and emits an electron (beta particle is the correct term but a beta particle is an electron). The electron has a lot of energy like a bullet from a gun. And like a bullet, it will lose that energy as it interacts with the environment, but cause changes and maybe damage as it loses the energy. Eventually it becomes a free electron just hanging around until some big boy picks it up.
    Meanwhile, what happened to the C-14 atom? Well the neutron that emitted the electron, instantaneously becomes a proton. That atom now has 7 protons and 7 neutrons. It is now a N-14 atom. N-14 is not radioactive. How many times did the one C-14 atom emit radiation? Once and only once.
    The are basically six factors that need to be accounted for when determining the hazard of a radioactive material. I have presented two above: half-life and quantity (number of atoms). Because of its relatively long half-life, if I put five atoms of C-14 in your body, chances are high that none of them will emit radiation in your lifetime.
    Test question: From the info I’ve given above, roughly how many atoms of U-238, which has a 4.5 billion year half-life, do you need to get 1 disintegration per second (1 Bq)? Radiation professionals are not allowed to respond! Bonus points for converting to gm.
    Nuclide Half-life Ci/gm TBq/gm 1 Ci =
    P-32 14 day 285,000 10545 3.5 ug
    Po-210 138 day 4,490 166 6 mg
    C-14 5730 yr 4.46 0.165 6 g
    Pu-239 24,400 yr .0613 0.0023 435 g
    U-238 4.5 E9 yr 3.3E-7 1.2E-8 6,600 lbs
    Note it takes very little mass of a short half-life nuclide to equal a Curie (3.7E10 Bq). If all the other factors I haven’t discussed are equal, then pound for pound a short half-life nuclide can be much more dangerous. If anyone wants, I can continue and try to simply explain the other four factors.

  118. Yeah I wrote a letter to the editor of my local paper several months ago about this, regarding the campaign they are colluding in to shut down the Vermont Yankee reactor over some tritium leaks, and explaining that the local lefty food co-op’s fruit section is a bigger radiation threat. They refused to publish, no big surprise.

  119. Edit note to Anthony: typoz —
    “reasearch” = research
    “Among the most naturally radioactive food known are” = foods
    ______
    The “lifespan” effects may be incorrect in sign:
    Taipei radiation study

    the observed health effects of the serendipitous contamination of 1700 apartments in Taiwan with cobalt-60 (T1/2 = 5.3 y). This experience indicates that chronic exposure of the whole body to low-dose-rate radiation, even accumulated to a high annual dose, may be beneficial to human health. Approximately 10,000 people occupied these buildings and received an average radiation dose of 0.4 Sv, unknowingly, during a 9–20 year period. They did not suffer a higher incidence of cancer mortality, as the LNT theory would predict. On the contrary, the incidence of cancer deaths in this population was greatly reduced—to about 3 per cent of the incidence of spontaneous cancer death in the general Taiwan public.

    (My emphasis)
    :)

  120. Moderator: I accidentally double clicked my first post and it did not like that. If it got through, please delete this post.

    Taught this stuff for 25 years. Many antinuclear folks make a big deal out of half-life, so I would like to address it here. Incidentally, substitute salt (KCl) has less chance of self-absorption and makes a great demonstration tool for Potassium-40 in our environment. Buy it at the grocery store when you buy your bananas.
    Imagine a single Carbon-14 atom and its nucleus of 6 protons, 8 neutrons. There are too many neutrons in the nucleus, and the atom is uncomfortable – imagine straining buttons on a too tight shirt. One day one of the neutrons pops. A tiny bit of the neutron flies off into space. This tiny bit is an electron (aka a beta particle for you professionals). The electron has a lot of energy like a bullet from a gun. And like a bullet, it will lose its energy as it interacts with the environment – eventually coming to rest. The energy it imparts will cause changes in the environment that may or may not be harmful. For example, the electron may break the hydrogen bond on a water molecule that is nearby. If the free hydrogen gets back together with the hydroxyl molecule, then no harm.
    Meanwhile what happened to the C-14 atom? Well the neutron that “popped” instantaneously becomes a proton. The nucleus now has 7 protons and 7 neutrons! It just became a N-14 atom. N-14 is not radioactive. How many times did the atom emit radiation? Just once and only once. All radioactive atoms emit their radiation only once. Some, like C-14, immediately become a non-radioactive atom. Some like Uranium-238 change to an atom that is radioactive and someday will also emit its radiation.
    Okay, our single C-14 atom will only emit its radiation once. When will it emit the radiation? We don’t know. Our atom has a 50-50 chance of emitting its radiation in a 5,500 year period. What is the atom doing the rest of the time until it “pops”. Nothing. It is acting like carbon, smelling like carbon, and going out on dates like carbon likes to do. No radiation emissions until the fateful day that it becomes a N-14 atom.
    (Radiation pros leave me alone on this next bit as I know I really simplify it.)
    How many C-14 atoms does it take to make 1 disintegration per second (1 bq)? It would take roughly 10,000 atoms to get 1 disintegration per year. 10,000 x 365 x 24 x 60 x 60 = 3E11 atoms. If I were to put five atoms of this relatively long half-life C-14 in your body, odds are that none of them would emit their radiation during your lifetime.
    I’ve presented two of the six factors that determine the hazard of a radioactive material: half-life and quantity (# of atoms). Presuming all other factors are equal, when the quantity is very small and the half-life is large, the risk is essentially zero. A short half-life nucleide can be more dangerous depending on the other factors.
    The following table gives you a clue as to the relationship of quantity and half-life plays out. A Curie (Ci) and a TerraBequrerel (TBq) are measures of the relative hazard. I handle a Ci or TBq very carefully.

    Nuclide Half-life Ci/gm TBq/gm 1 Ci =
    P-32 14 day 285,000 10545 3.5 ug
    Po-210 138 day 4,490 166 6 mg
    C-14 5730 yr 4.46 0.165 6 g
    Pu-239 24,400 yr .0613 0.0023 435 g
    U-238 4.5 E9 yr 3.3E-7 1.2E-8 6,600 lbs

    As the half-life increases, it takes a lot more mass (# of atoms) to give a Ci or TBq worth of radiation.

    One critical factor in determining the hazard of a radionuclide is its chemical form. The uranium used in a powerplant is in a chemical form that if you swallow it, likely you will poop out greater than 99% within 3 days. However if this is ground into an aerosol with a low AMD number (<10) and you breath it in, then about 10 – 20 % will lodge in the lung with eventual transport to other parts of the body. If our body likes the chemical form, it will be taken up. If not, then we poop, pee and or otherwise excrete the material fairly quickly. Some other contributors mentioned nuclides that are analogous to chemicals which our bodies like. Radium and Cesium are a couple of those. I might swallow a source of radium encapsulated in plastic that I wouldn't worry two hoots about, but I handle radium salts very, very carefully.
    Other factors are the type of radiation, the energy of the radiation, how it gets deposited, and whether or not it decays to another radionuclide

  121. What I find surprising is the huge amount of misinformation that exists about radiation. I find that not a single patient who’s refused to get a chest xray because of “dangers of radiation” knows about K40. These same patients will have no qualms about flying to Australia where they receive more radiation during their flights than during the chest xray!

    The most devastating study debunking the no-threshold assumption was published in spring 2004 in the Journal of American Physicians and Surgeons. It documented the effect of accidental contamination of structural steel with Co-60 which was used to construct apartment buildings. (link: http://www.jpands.org/vol9no1/chen.pdf). The expectation was increased deaths from cancer whereas the exact opposite occurred: 242 deaths were expected based on age standardized cancer mortality and 7 were observed.

    What I find most surprising is the minimal amount of publicity this has received with the only article referencing it in the MSM being a recent article in the Financial Post which was given in a previous comment. I’ve printed out a copy of the JAPS article to give to my radiationphobic patients who sometimes will be ready to spend $1500 to get an MRI rather than an xray.

    Thanks for the info regarding the CT scan/lung cancer link Rational Debate; another piece of information I can give to the radiationphobic. Perhaps I should shock them with some of the pottery I painted years ago (when I had time for such diversions) using Uranium oxide to make a nice yellow underglaze paint. When I get around to buying a geiger counter will see how radioactive those ceramic pieces are.

  122. There are some excellent comments regarding radiation risk. To add to them…

    There is a huge controversy in the radiation world regarding low dose radiation. With thousands of studies demonstrating low doses can have a beneficial effect, then it rapidly becomes a moral and ethical question of whether or not we should limit or try to eliminate low dose radiation. For example, if a low dose gives one susceptible individual a cancer, but prevents hundreds of thousands from getting a cancer (research seems to indicate this is possible), where should the limits be set? In other words, if we set the limits extremely low, like we do now, you might get a cancer but that one susceptible person may not. It is a huge dilemna and has large impact on the costs of protecting the public from radiation. The present day limits are set based on the precautionary principle. However, if low doses are good for us, then this precautionary principle may harm more than it helps.

    The 10 mRem equals so much risk concept is a scientific joke. It is derived, based on precautionary principle, from high dose radiation effects. There are no (none, zip, nada) studies that show low dose radiation has any deletorius effect on our life spans. Yes, there are lots of sttudies showing deletorius effects at the atomic and cellular level, but too often overlooked is the amazing ability of our cells and organs to repair the deletorius effects (which exercises the repair mechanisms). Compared to other things, low dose radiation is very weak in causing harm at the microscopic level. Our bodies have been handling low dose radiation ever since we were mudpuppies. Without the small assault of low dose radiation, would those repair mechanisms wither? Research seems to indicate this is so. Bernard Cohen at the U of Pittsburgh has demonstrated that the level of Radon that the EPA considers hazardous (4 – 20 pCi/l) seems to be better for us than getting less than 4 pCi/l. Go figure, but no one has been able to refute his work, and more than a few have tried.

  123. Don’t forget, that background radiation is the reason we are here in the first place. Without it the mutation rate in DNA would be much less and evolution would either have been much slower or not occurring at all.

    I love bananas! But that’s because I’m a chimp, really.

  124. RE: Radioactive Potassium is in the Interior of the Cells of All Plants and Animals

    George E. Smith says on February 16, 2011 at 1:43 pm:

    K40 is a beta and gamma emitter, with a half life of 1.3 E+9 years. It is 0.0118% of natural Potassium, and emits an electron with 1.32 MeV energy. It can also capture an orbital electron and that is a 1.51 MeV event. The electron emission (beta decay is accompanied by a 1.46 MeV gamma.

    The Beta electron is not likely to penetrate far into organs or cells; the gamma is a bit more of a problem

    A human with a mass of 70 kg has 245 g of K of which 29 mg is the K-40 isotope. This mass of radioactive K produces ca 320,000 disintegrations per minute.

    Ref: The Fire of Life” by Max Kleiber p 361.

    The 1.32 mev beta particle could break ca 300,000 H-O bond (bond energy ca 4 ev) of water molecules to give a hydrogen radical and hydroxyl radical. The hydrogen radical could readily grab a hydrogen atom from an adjacent water molecule to produce another hydroxyl radical and a molecule of hydrogen gas. Thus ca 600,000
    highly reactive hydroxyl radicals could be produce per minute and these could go on to attack the various organic molecules in cell such as DNA.

    If the beta particle would happen to strike an organic molecule, it would be blown to bits. After ejection of the beta particle, the K-40 atom turns into a neutral argon atom which recoils with 2.8 mev of energy and which could possibly smash more organic molecules to bits.

    I suspect that many spontaneous cancers in humans and mutations in plants and aminals may be due to radioactive K.

    The concetration of K-40 in Pacific pink canned salmon (low salt type) is 400 ppb by wt. I’m not going to worry about a few ppb of any pesticide in salmon.

    What would the greenies do if they learned of all food is contains substantial amounts of K-40. Hopefully they would stop eating and starve to death.

  125. kadaka (KD Knoebel) says:
    February 16, 2011 at 9:24 pm

    From Max Hugoson on February 16, 2011 at 7:58 pm:

    C. “Salt Substitute” or Potasium Chloride, really raises the GM Counter nicely. [...]

    Note the recent push with foods to reduce sodium intake, by replacing common sodium chloride with “sea salt.”

    The push is originating from the WHO, which happens to be an UN “child” much like the IPCC.

    But just wait. Sea salt is NaCl, sodium chloride. What replacement is that? More UN-grade science?

  126. Leg said on February 17, 2011 at 12:30 am:

    I see the table in the previous post looks lousy. How do you do a good table posting to a site like this?

    Under the Comment box you write in, are the usable HTML tags and attributes. Note the “code” option.

    Nuclide__Half-life__Ci/gm____TBq/gm__1 Ci =
    P-32_____14 day_____285,000__10545___3.5 ug
    Po-210___138 day____4,490____166_____6 mg
    C-14_____5730 yr____4.46_____0.165___6 g
    Pu-239___24,400 yr__.0613____0.0023__435 g
    U-238____4.5 E9 yr__3.3E-7___1.2E-8__6,600 lbs

    That’s “code” like computer code. It uses a fixed-width font, all characters the same width. Space things out with underscores, as multiple spaces are auto-collapsed to a single space. Bracket the section with “code” above and “/code” below (using the left/right arrows of course). Then you can get as close to a readable table as possible.

    However, unless you’re very good with character counting and very confident with your work, a Preview function is basically needed and desired to get the layout right with everything lined up and sufficient spacing for clarity. I used mine extensively for the reworking of your table above. If you want your own Preview function, you have to install it. WUWT is hosted on wordpress-dot-com, and such a function cannot be added to a wordpress-hosted blog site as wordpress-dot-com doesn’t offer one for sites as this. Thus to get Preview, you install CA Assistant, available here:

    http://climateaudit.org/ca-assistant/

    It also provides additional aides for nice HTML formatting. Caveat: Not all of the extra buttons are enabled on WUWT, just what’s listed as allowed under the Comment box. The non-enabled will look good on Preview but won’t be picked up when you Post Comment.

  127. George E. Smith says: February 16, 2011 at 1:43 pm
    Well I wouldn’t put a lot of stock in that use a truck load of bananas to hide your nuke in.

    And just think of the gooey mess if it accidentally detonated.

    Great thread.
    Morton’s Lite Salt™ substitutes 50% potassium chloride for sodium chloride. I guess the slightly metallic taste is a radiation effect.

  128. AnonyMoose says:
    February 16, 2011 at 10:46 am
    “There are about 1,200 beta particles per second produced by the decay of 14C. However, a 14C atom is in the genetic information of about half the cells, while potassium is not a component of DNA. The decay of a 14C atom inside DNA in one person happens about 50 times per second, changing a carbon atom to one of nitrogen.”

    Jim G above said:
    “Potassium is a beta- (electron) emitter.”

    OK So, beta-decay is the emission of an electron?
    And that can turn C14 into nitrogen?
    What’s wrong with this picture?

  129. in aus in the 50s? they made some stunning apricot coloured glass ware…it is really pretty.
    however it appears the sand they mined for it had a high radium content, all true product glows neon orange in a black light.
    its now named “radium glass” and is very collectible, and also priced beyond the average!

  130. From Josualdo on February 17, 2011 at 3:48 am:

    But just wait. Sea salt is NaCl, sodium chloride. What replacement is that? More UN-grade science?

    Warning: Severe lack of knowledge of contents of sea water detected. Deploying relevant Wikipedia link:

    http://en.wikipedia.org/wiki/Sea_salt

    There are many distinctive “sea salts” of different colorations and textures, as known among cooking aficionados. And they can have them. Review the ion table at link. By concentrating on just the sodium in common table salt, reductions in sodium can be claimed by using “sea salt” where the sodium salt is partially displaced by other salts like calcium, magnesium, and potassium salt. Heck, you could make a soup with even greater salinity using “sea salt” instead of table salt, and still claim a sodium reduction.

    While I would like to blame UN Science for that, it’s actually more like PR Science. ☺

  131. In the late 1970s I wore a wrist watch that had belonged to my grandfather. One day during a high-school science class the teacher produced a geiger counter. I remembered reading somewhere that old watches used to have radium in the luminous paint. Sure enough, the watch was radioactive.

  132. It just came to me that Harry Chapin had a song about a truckload of bananas called “30,000 Pounds of Bananas”. Based on a true story, a truck carrying 30,000 lbs of bananas crashes after the driver fails to shift to low gear on a steep descent. That’s one big radioactive mess to clean up.

  133. Interesting twist on our being bathed in radiation. My only quarrel with the post is the application of a linear, no-threshold (LNT) to cancer risk from radiation exposure. The 2 NCRP members that were on my doctoral committee didn’t agree with that concept at low doses.

  134. Many years ago a group in the UK issued a report showing the occurrence of certain types of cancers near “military establishments” due to the increased levels of radiation in the local area. There followed all the usual brouhaha over the control of radioactive materials in the military etc etc.
    The sites were not revealed till later when it turned out they were all mediaeval or older and the radiation was from the rocks on and from which they were made.

    James.

  135. Here is another fact that makes me crazy: opponents of irradiating food have succeeded in terrorizing enough of the public so that it isn’t a routine procedure, thus leading to thousands of cases of food poisoning and not a few deaths, all of which are preventable.

  136. High energy radiation in space can be explained by the presence of electric currents in plasma, so for cosmology electrical banana is bound to be the very next phase.

  137. “However, I would NOT live next door to a Nuclear Power plant as I would not personally accept the increased risk based upon their history of incidents.”

    Good lord, you’re innumerate.

  138. “It just came to me that Harry Chapin had a song about a truckload of bananas called “30,000 Pounds of Bananas”. Based on a true story, a truck carrying 30,000 lbs of bananas crashes after the driver fails to shift to low gear on a steep descent. That’s one big radioactive mess to clean up.”

    As the EPA has claimed authority over spilled milk (due to the oil content and their authority over oil spills), perhaps the NRC needs to take authority over banana spills?!

  139. Chris says:

    February 16, 2011 at 7:38 pm

    Ric Werme says:

    “Once radon decays, it emit two more alphas and betas very quickly, hangs out at 210 Pb for a while (22.3 year half life) and that emits an alpha and two betas before stopping for good at 206Pb.”

    Forgive my ignorance, but how can something emit an alpha and still remain the same element?

    It cant, alpha decay means the nucleus loses 2 protons and 2 neutrons, thus atomic number goes down by 2.

    Also Rick’s description of Pb-210 decay was a shorthand, Pb-210 decays by beta (22.3 yr half ilf) to Bi-210, which promptly decays by beta (t1/2 5 days) to Po-210, this is the alpha emitter of Alexander Litvinenko fame, which decays with the 138 day t1/2 by alpha decay to Pb-206 which is stable, the end of the U-238 series.

    Po-210 was the radiotoxin of choice for the Russians since (a) it is the only alpha emitter with purely soft tissue biodistribution (not a boneseeker) thus the most radiotoxic, and also a remarkably pure alpha emission with negligible x-ray / gamma emission, thus no external detection by geiger counter.

  140. Physics for all. I took what I thought was an easy ace science elective called Energy and the Envriornment when younger and greener. All kids and greenies are know-it-alls and the physics instructor was pro-nuke recently after TMI. So grateful for that class – not just for giving me the ability to begin to understand the nature, benefits and limits of various energy sources, but to dissect the public “witch” of the moment.

    Radon and bananas and granite – Oh My!! And radioctivity in all other sorts of household sources. We may laugh now, but there is a drastic solution for every unjustified fear. Explaining dosages /exposures just doesn’t capture the attention like a scare does. And once scared, the explanation can cause more fear. Try telling someone scared of germs that they’re everywhere and that they are certainly breathing some in whenever they go in a kitchen or a restroom.

  141. kadaka (KD Knoebel) says:
    February 17, 2011 at 4:55 am

    From Josualdo on February 17, 2011 at 3:48 am:

    But just wait. Sea salt is NaCl, sodium chloride. What replacement is that? More UN-grade science?

    Warning: Severe lack of knowledge of contents of sea water detected. Deploying relevant Wikipedia link:

    Oh, I see. Thanks a bunch. PR science it is! Indeed most of it ends up being NaCl anyway, displacement here and there (and sodium sulphate, that’s a funny one).

  142. bfl,

    My summary of the TMI health studies:

    .

    A little more reading for the interested, Three Mile Island Accident Health Effects. This is really interesting reading if you go through the whole article in Wikipedia. The initial Government report determined that nothing much happened health wise. Either fear factor, class action law suit piling on or hyper awareness caused residents to report more health problems which started another health study. That study showed an ~ 0.14 % +/- 0.07% increase in all cancer cases which is barely statistically significant. A study in 2008 found that thyroid cancer rates in the county of the reactor were 1/3 the rate of neighboring counties. Like the low level radiation dosages may have acted like a thyroid cancer vaccine. Pretty fascinating stuff but health statistics are not in my job description.

  143. BFL: most of your 1:16 post has been dealt with by others. I do find it amusing that you’re quoting CCNR, a website and antinuclear group run by a high school math teacher with no expertise whatsoever in any field of nuclear science, nuclear engineering or radiation health physics. Your claims however about health effects from TMI are bogus. These claims were all tested in court in the 1990s. None were found to have any substance whatsoever.

  144. Slacko says: “OK So, beta-decay is the emission of an electron?
    And that can turn C14 into nitrogen?
    What’s wrong with this picture?”

    Leg response: Nothing wrong with the picture at all. It’s what happens. Read my posts previous to yours. C-14 has 6 protons and 8 neutrons in its nucleus. Upon decay, one of the neutrons ejects mass in the form of an electron(beta particle). That neutron instantaneously becomes a proton. The conversion of a neutron to a proton now causes the nucleus to have 7 protons and 7 neutrons which is N-14. N-14 is not radioactive. Like any radioactive atom, this C-14 atom emitted radiation once and only once.

    Neutrons, protons and electrons have mass. If you look at the mass difference between a proton and a neutron, you will see it is almost the mass of an electron. The mass of a proton and an electron together equal the mass of a neutron (there is a teeny fractional difference not worth mentioning unless you want me to get into atomic physics a lot deeper).

    Sometimes a proton captures an electron and becomes a neutron. When this happens, there is typically an emission of gamma energy. I-125 does this. At the instant of decay (gamma emission) the I-125 atom becomes a Te-125 atom. This atom will no longer emit radiation. Decay mechanisms usually involve Einstein’s formula which says mass is energy and energy is mass as there is some conversion of mass to energy or vice-versa.

    If you have a pile of C-14 and put a radiation detector on it, you will see fewer and fewer clicks occurring as time passes because each click of the meter means a C-14 atom has become N-14. Hence there are fewer C-14 atoms as time goes on.

  145. Further to the query from Chris 7:38 pm:

    “Once radon decays, it emit two more alphas and betas very quickly, hangs out at 210 Pb for a while (22.3 year half life) and that emits an alpha and two betas before stopping for good at 206Pb.
    Forgive my ignorance, but how can something emit an alpha and still remain the same element?”

    I’m not sure if anyone has given a good enough answer to an excellent question from Chris: perhaps I can try…

    The nucleus of an atom contains both protons (positively charged) and neutrons (no charge). Which element an atom belongs to is determined SOLELY by the number of protons alone.
    Thus, hydrogen has 1 proton. Most of the hydrogen in the universe has no extra neutron.
    Hydrogen with 1 proton (always) but also with one neutron is called Deuterium and is stable.
    Hydrogen with 1 proton (always – that defines hydrogen) and 2 neutrons is Tritium and is radioactive, emitting a beta particle i.e an electron.

    The nucleus does not contain free electrons. It only contains protons and neutrons. In Tritium (and all other beta emitters) the elctron comes from the breakdown of a neutron (neutral) to an electron (negative) and a proton (positive). Charge is conserved and the proton stays in the nucleus. Thus, the nucleus (which used to have only 1 proton and 3 neutrons) now contains 2 protons and 2 neutrons. Any atom containing 2 protons is, by definition, Helium. Helium (with 2 protons) and 2 neutrons is stable and the most common form of Helium (often referred to as He-4 for the 2 + 2 particles in the nucleus). [Helim also exists in nature as He-3 with 2 protons by definition but only 1 neutron.]

    To recap. Beta decay changes a neutron into a proton and hence changes to the element with an Atomic Number (number of protons) that is one greater than before.

    An alpha particle is a He-4 nucleus (i.e. without any electrons). Thus, emitting an alpha particle lowers the atomic number by 2 and reduces the number of nucleons (protons + neutrons) by a total of 4.

    Thus, Pb-210 has 82 protons and 210-82 = 128 neutrons.

    Its decay goes through a series of stage:
    1) Loss of 1 beta particle thus changing a neutron into a proton. The nucleus now has 83 protons and is Bismuth. The number of nucleons stays the same – 210. Thus, Bi-210 is formed.

    2) Bi-210 now undergoes the loss of another beta particle from the conversion of another neutron to a proton. Protons now number 84 which is Polonium. Thus, we now have Po-210.

    3) Po-210 now looses an alpha particle – 2 protons and 2 neutrons. The number of protons drops by 2 from 84 (Po) to 82 (our old friend, lead Pb). The total number of nucleons lost is 4 so this is Pb-206.

    So. Loss of 2 beta particles and one alpha (in any order although the order I’ve given is correct for Pb-210) takes you back to the element you first thought of but 4 nucleons lighter.

    I’ll try again if anyone doesn’t follow this! (Assuming anyone wants me to!!)

    The key is that the element present is determined totally by the number of protons.
    Pb-210 to Bi-210 beta – increases protons by 1.
    Bi-210 to Po-210 beta – increases protons by a further 1.
    Po-210 to Pb-210 alpha – REDUCES the number of protons by 2 and nucleons by 4.

    IN EFFECT, four neutrons have been lost – 2 converted to protons + 2 lost in the alpha particle.

  146. Alan Bates: great explanation but one oops…

    instead of “Po-210 to Pb-210 alpha – REDUCES the number of protons by 2 and nucleons by 4. ” it should be “Po-210 to Pb-206 alpha – REDUCES the number of protons by 2 and nucleons by 4.” So Pb-206 not Pb-210. Of course Pb-206 is non-radioactive.

    We should get together and collaborate on these explanations of how radiation works. I like your style.

  147. I’ve always found it similarly amusing that smoke detectors contain radiation sources (americium, I believe). This page:

    http://www.epa.gov/rpdweb00/sources/smoke_alarm.html

    gives the activity of a smoke detector as several microcuries. I wonder how many of the people who wet their pants over the radioactive iodine from Three Mile Island have since voluntarily purchased and installed much more substantial sources of radiation in their homes.

  148. Hi Leg (and Mods.)

    Thanks for spotting the “deliberate” mistake! (It was after midnight, my time.)
    My (admittedly LONG) explanation overlapped a number of different posts with good comments. The delay in moderation didn’t help (NOT, please NOT a complaint to the Mods. who do an excellent job but the unavoidable delay means that a lot can happen between comments).

    I worked in a civil nuclear power plant as an industrial chemist and all of this sits well with the Radiochemistry I learnt and re-learnt during my education and my career. I am a strong believer that I you cannot explain something, you don’t understand it

  149. Let’s not forget the oh so common radioactive exit signs. :-)

    http://www.nrc.gov/reading-rm/doc-collections/fact-sheets/fs-tritium.html

    More than 2 million tritium EXIT signs are estimated to be in use in the United States. The signs do not require electricity or batteries, and are commonly used in areas where it is difficult to install electric signs (eg., above doors). They serve a safety function by remaining lit during power outages and emergencies.
    Exit Sign Image

    The tritium gas is contained in sealed glass tubes. The insides of the tubes are lined with a phosphor. Low-energy Beta particles emitted by the tritium bombard the phosphor, causing it to glow.

    There are a couple ways to determine whether an EXIT sign near you contains tritium. The device should contain a permanent warning label that mentions tritium (H-3), displays the three-bladed radiation warning symbol, and states “Caution-Radioactive Materials.” If the label is not readily observable, try extinguishing all lights in the vicinity. If the word EXIT is green, the sign contains tritium. If all four letters in EXIT are fully lit, the sign is working properly. If not, the sign may be damaged.

    Tritium emits low-energy beta radiation that cannot penetrate a sheet of paper or clothing. If inhaled, it leaves the body relatively quickly. Tritium gas is odorless, colorless and tasteless, and is lighter than air.

  150. Russ says:

    February 17, 2011 at 6:41 am

    Interesting twist on our being bathed in radiation. My only quarrel with the post is the application of a linear, no-threshold (LNT) to cancer risk from radiation exposure. The 2 NCRP members that were on my doctoral committee didn’t agree with that concept at low doses.

    Agree strongly, the LNT theory of carcinogenesis is very much in the same category of politically driven pseudoscience as CAGW (carbon-dioxide anthropogenic greenhouse warming). It is deeply reductionist and inductive, built primarily on mathematical / computer modelling, is false, and exists to serve a political objective.

    In the very lowest dose range of ionising radiation, there is more evidence for a slightly health positive effect of radiation than of any carcinogenic (or any other such as mutaenic) risk. You cant extrapolate from the petri-dish to the organism any more than you can from a computer model to the global climate.

  151. The LNT theory of carcinogenesis for low dose radiation would be difficult to prove because of other factors at those levels. But cells are complex and sensitive to DNA damage. If the organism is lucky, an overly damaged cell will die by apoptosis or other programmed cell death with no further damage done. If not, then possibly a tumor or cancer will arise from one or more cells run a muck. There are many, many known and proven carcinogens from simple physical irritation to chemical and radiation. Therefore it just appears logical to me that based on the mechanisms of cell DNA damage involved that one should not go out of the way to cause that damage. This includes smoking, playing with asbestos, benzene, radium, the sensor in a smoke detector, or getting unnecessary X-rays/CAT scans. Of course there are exposures that can’t be entirely avoided, food aflatoxins (although it wouldn’t hurt to eat less peanut butter and corn), mercury from coal ash or large fish, breathing the portion of gasoline vapors that contain benzene, and radioactive compounds in food.
    Sometimes a paycheck requires that one be exposed to some radiation or other hazards such as those people in the nuclear arms industry. But this is the reason the technicians go away from the X-ray machine in a dentist or doctors office as there is no benefit/reward to the excess exposure and the harm can be catastrophic.
    I reiterate, that unlike AGW which can, if it exists, be adapted to, the consequences of loose thinking about hazardous substances, including radiation, can be quite lethal in the long run depending literally on your luck.

  152. Boris G.;
    Perhaps the reason the radiation benefit study hasn’t received much publicity is indicated by scanning the list of co-authors: it is considered sort of ‘Wu, Wu’.
    ;)

    And it shows many of the commenters here are still in the grips of reflex rad fear. The real point of this posting is that avoiding radiation is an exercise in foolish futility in all but exceptional cases.

  153. P.S. re my above, the phlogiston comment is a kind of demonstration: “In the very lowest dose range of ionising radiation, there is more evidence for a slightly health positive effect of radiation than of any carcinogenic (or any other such as muta[g]enic) risk.”

    Up to 100mG/y, with a 97% reduction of cancer incidence, is hardly “the very lowest dose range” with “a slightly health positive effect”. It’s strong moderate exposure, with overwhelmingly positive health effect.
    A banana a day hardly makes a dent! Even a dozen a day wouldn’t be enough.
    :)

  154. @ Brian H.
    You might be interested in this:
    http://www.phyast.pitt.edu/~blc/LNT-06 fig.rtf

    Which would indicate that low or even moderate levels of radiation MAY reduce cancer risk through a proposed increased immune function by stress resulting from radiation damaged cells perhaps similar to “Coley’s Toxins”.

    http://en.wikipedia.org/wiki/William_Bradley_Coley

    However, I would (personally) think it more logical to produce this stress through exercise or to increase cell repair efficiency with herbal supplements/vitamins rather than whacking cells with atomic bullets or bacterial poisons and hoping the immune system kicks in enough to kill cancer cells too.
    Interestingly many commenter’s will argue for ignoring controllable exposure to radiation or even for intentional exposure but I have found few people to date that will try the following even though it appears to have a dramatic affect on some immune system diseases:

    http://en.wikipedia.org/wiki/Helminthic_therapy

    I guess radiation is psychologically less repugnant than worms.

  155. Brian H says:
    February 19, 2011 at 2:56 pm
    P.S. re my above, the phlogiston comment is a kind of demonstration: “In the very lowest dose range of ionising radiation, there is more evidence for a slightly health positive effect of radiation than of any carcinogenic (or any other such as muta[g]enic) risk.”

    Up to 100mG/y, with a 97% reduction of cancer incidence, is hardly “the very lowest dose range” with “a slightly health positive effect”. It’s strong moderate exposure, with overwhelmingly positive health effect.
    A banana a day hardly makes a dent! Even a dozen a day wouldn’t be enough.
    :)

    Thanks for correcting my typo – or mutation – of mutagenic!
    Yes indeed I rather understated the case for hormesis (I’m British so understatement is probably genetic) – but a few minutes on PubMed central will produce many papers showing consistently increased longevity, stimulated immune function and decreased tumour incidence from ionising irradiation of mice and other organisms. It appears – as BFL mentions – that low dose irradiation induces a surge of immune response, due to cell damage, heat shock proteins etc, and this “surge” enhances the continual activity of the immune system in mopping up precancerous cells. So the net result is actually tumour suppression. This would be unquestioned orthodoxy if it were not so politically inconvenient.

    Here’s a paper I just found on PubMed (took about 10 seconds) (mice+immune+Gy):

    Int J Radiat Biol. 2011 Feb;87(2):202-12. Epub 2010 Nov 10.
    Anti-neoplastic and immunostimulatory effects of low-dose X-ray fractions in mice.
    Nowosielska EM, Cheda A, Wrembel-Wargocka J, Janiak MK.

    Department of Radiobiology & Radiation Protection, Military Institute of Hygiene & Epidemiology, Warsaw, Poland.
    Abstract
    Purpose: The exploration of immune mechanisms of the tumour-inhibitory effect of exposures to low-level fractions of X-rays. Materials and methods: BALB/c mice were exposed to whole-body daily irradiations with 0.01, 0.02, or 0.1 Gy X-rays per day for 5 days/week for two weeks. Then, mice were intravenously injected with L1 tumour cells, killed 14 days later, and neoplastic colonies were counted in the lungs. Natural killer (NK) cell-enriched splenocytes and activated peritoneal macrophages (Mϕ) were collected and cytotoxic activities of these cells against susceptible tumour targets were assayed. Concanamycin A (CMA) and antibody against the ligand for the Fas receptor (FasL) were used to inhibit the NK cell-mediated cytotoxicity. Production of nitric oxide (NO) was quantified using the Griess reagent. Secretion of interferon-γ (IFN-γ), interleukin-1β (IL-1β), interleukin-12 (IL-12), and tumour necrosis factor-α (TNF-α) was measured using the enzyme-linked immunosorbent assays. Results: All the exposures to X-rays significantly reduced the number of the induced tumour colonies and enhanced cytotoxic properties of the NK cell-enriched splenocytes and activated Mϕ. Conclusion: Suppression of the growth of pulmonary tumour colonies by irradiations of mice with low-dose fractions of X-rays may result from stimulation of anti-tumour reactions mediated by NK cells and/or cytotoxic macrophages.

    BTW IJRB is a high profile international radiation biology journal, I was fortunate to publish in it a few times myself (look for Salmon PL).

  156. re: REPLY: get your own blog and you can talk about Chernobyl all you want, this thread is about Potassium-40 in bananas. – Anthony

    Now, now, Anthony. He wants to talk Chernobyl, let him

    Point out that that is what happens when socialism runs the plants. The design was by the man who curried the most favour in the party, the techs were those that were not politically suspect

    What happened at Chernobyl would not have in an American reactor, let alone a Canadian Candu reactor.

    Watermelons (green on the outside, red all the way to the core) are not interested in your interests, they are interested only on their historical inevitability.

  157. @BFL;

    “In Dauphin County, where the Three Mile Island plant is located, the 1979 death rate among infants under one year represented a 28 percent increase over that of 1978, and among infants under one month, the death rate increased by 54 percent.”[4]

    I chased after this cite for a bit, it resolves (allegedly) to a paper in an issue of Bulletin of the Atomic Scientists, well known as a completely objective and non-political organization…

    Sadly, the article apparently can’t be found even on their site.

    So, what I’d like to know is what raw numbers the cited “28%” and “54%” increases actually represent? If you’d had four deaths in 1978 and five in 1979, you’d have a 25% increase right there. Also nothing close to a statistically relevant number.

  158. Any chance we can have a “Update: ….” to this article relating to the Japanese reactor leaks.. specifically a reasonable guess at the number of bananas the people within the 20km evacuation zone might have encountered?

  159. The Fukushima 50 were exposed to >1,000,000 BED
    The peak radiation at Fukushima was >4,000,000 BED/hour
    People outside of the immediate area <100 BED

  160. Earlier this year, I read that Pakistan is increasing its nuclear arsenal from 100 bombs to 200. This is a country that has rolling blackouts as a matter of course. So I thought, that is idiotic – they have an intention to use those bombs. So I went on Amazon and bought 25 courses of potassium iodide. Then I found the mother lode. Nasco in Wisconsin sell 500 gram bottles of potassium iodide for about $50. So I bought a kilo – enough for 720 people. It works out at about $0.02 per person.

  161. Historically, the progression in scientific/technological innovations by man progresses from the large and clumsy to the small and more refined. Some of this comes naturally via many iterations through trial and error, and some comes from new insight gained from increased understanding of a phenomenon.

    The day may come when we can harness nuclear energy on a small scale without the complication of highly radioactive waste. (A few scientists have postulated the transmutation of elements in biological systems; however this is regarded as fringe science similar to cold fusion.)

  162. There is certainly a fear of radiation in the general public, but is that fear misplaced I think what is happening in Japan shows it is not.
    There are a number of different scales for radiation levels and yes Bananas do emit radiation as do things like florescent paint and CRT monitors. In a reactor with it safety systems intact you would expect find little radiation, that is what safety measures are for. As do the tracers used in CAT scans
    But levels last Thursday at the main problem site in Japan went considerable above safety limits and bananas as a scale
    Your banana is 0.1 μSv, but on that same scale normal background radiation is
    2.4 millisievert (mSv) per year on the same scale as your banana that is 2400 μSv (a lot of bananas)
    What are the levels at the worst reactor in Japan, the peak on Friday was 20 millisievert (mSv) per HOUR or 20,000 μSv, multiply that number by 10 (as your banana is only 0.1 μSv) to get the number of bananas you would have to eat to get the equivalent dose of radiation.

    A Handy radiation cross calculator

    http://hptech.org/nuclear/convert/sievert.html

  163. 1 banana = 1microsievert

    Highest radiation level = 400,000 microsieverts/hour

    x 24 hours a day, 365 days a year.

    Assuming an average banana weighs 120 grams – then:

    0.12 x 3504000000 = 420480000 kg or 420480 metric tonnes of bananas.

    Or approximately the weight of one of one of the biggest ships in the world, in bananas.

    Someone should check my working, but I think that’s right.
    “Great is the power of steady misrepresentation, but the history of scienc

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